Small note: with open qualifiers on October 23rd, we've got pretty much no major tournament action happening before the invites should be known. That means that, outside of some group play in Dream League, we're not gonna see any of these teams play another game until after the invites go out.
The Format
We know we're getting some type of group stage that takes place over a two day time period, that the group stage is for seeding only (everyone makes the bracket stage), and it's a single elimination best of three until the finals, which are best of five. This is quite different from previous valve events and majors in that we're using a single elimination instead of a double elimination system which decreases the number of games and makes every series an elimination series at the expense of a lower probability of the best team actually winning the event outright. I think this is a decent change of pace, and while I don't think all majors will be this way from now on the single elimination format hasn't received much love in Dota 2 recently, so it's nice for some variety.
It should be noted that this also makes the group stage both more and less important: it's more important in the sense that if you get a team like EG in the first round you're probably screwed, BUT it also means that your slate it wiped clean after group stages, which is nice in that you can shake off a bad group stage and make a killer run through the main event if you pull it all together (similar to Fnatic at TI6).
Invites
Because major championships don't have a wildcard stage (and with a two day group stage, I don't expect this tournament to have one either) along with the fact that we have four regions to get teams from, we'll probably have either 4 or 8 direct invites with the rest of the teams having to go through qualifiers (2 or 3 each, depending on the number of invites). That said, it's possible we might see a 6 team invite list if Valve separates CIS from Europe or does something else wonky, but that would set a precedence that's harder to work around in other tournaments, so I think that possibility is unlikely.
Depending on either 4 or 8 invites, the scenarios break down pretty differently. I'll list the possible teams below and my reasoning for each falling where they do.
The Guaranteed
This teams should be there no matter if there are 4 or 8 invites.
Wings - The defending TI champions will surely be at the next major, no way Valve leaves them out.
Evil Geniuses - The winners of the only premium tournament we've had so far this year (MDL) and the team with arguably the strongest post shuffle roster, they will definitely make their presence known in Boston.
Digital Chaos - This one is a little tricky, as they haven't played in a single tournament so far with their new roster. That said, they did get second place at TI and had minimal roster changes, so this team should have some pretty clear sailing for a direct invite.
On the Edge of 4 and 8
These teams have a chance at the 4th slot in a direct invite system, and will also certainly be there if there are 8 invites instead of 4.
Fnatic - 4th place at TI with what can only be considered a synderella (xD) run, they make a good argument for a direct invite. Even though only two players of that TI6 team return in Mushi and Ohaiyo, they were bolstered by the addition of Demon, Eyyou, and Raven from the 8th place finishing TNC. However, they did have a not so stellar performance at their only tournament so far this year (MPGL), which puts them in potential danger of not receiving a direct invite if Valve only gives out 4.
Newbee - The 2nd place team at MDL, this team has a completely new feel to their roster. Gone are the mainstays of Hao and Mu and the ever popular Chuan as we enter the new age of Sccc and uuu9. While this team has undergone some major shifts in roster, they still have Kaka at the helm and they have been one of the most succesful Chinese teams so far in this current season. Their second place performance at MDL was fun to watch (with a series victory over EG in the bracket stage, no less) and should have earned them consideration for a direct invite, even with just 4 teams.
Probably there with 8 Invites
This team should be at the Boston major as a direct invite if there are in fact 8 invites rather than 4.
OG - A nice performance at MDL has done a lot for this team, and they are probably Europe's best besides potentially the new Team Liquid. Ana showed himself to be the real deal (at least on OD), and they played some pretty crisp Dota for a team with a brand new to offlaning offlaner in S4 and a brand new (mostly) to competitive dota Ana. Jerax is a good fit for this roster, and they had some nice performances in individual games at MDL, though they eventually fell to Newbee and EG.
Now Things Get Weird - The Last Two Spots
These are the teams that have played and performed well enough in recent history to basically assure themselves of direct invites should the number of invites total 8. Beyond the 6 above, things start to get a little weird as far as invites are concerned. Here are the teams that stand a potential chance of receiving one of the two remaining invites should 8 teams be invited.
Team Secret - While their MDL performance was somewhat erratic, they did play some of the best games of the tournament with some pretty big comebacks in the group stage, particularly game 1 against Newbee. In addition, their roster has Puppey, paragon of Valve events, as well as 2 players that finished in the top 6 and one player that finished in the top 4 of TI6. They could make a somewhat convincing case of receiving a direct invite for the Boston major, but finishing 4th at MDL out of 8 does bring some pause, and is the reason why I don't consider them a lock for a direct invite.
Team Liquid - They haven't played a single match, and they won't until after the invites go out (except potentially in dream league round robin play). Without the current results and with an 8th place TI finish, they would be hard to pencil in for a direct invite except for the fact that this team played extremely well during the entirety of last season, and they added one of the top 5 players in Dota today in Miracle as their new mid player, replacing Fata. This team is probably very good, it's just a shame we haven't had a chance to see it yet.
XTCN - Valve may decide to go in a different direction and reward a team that participated in a Major (but not premium) LAN and won it with some pretty awe inspiring play. They have DJ as a support player, a TI6 4th place finisher, and they have one of the more dynamic young players in Dota 2 today in Abed in the middle lane who proved his mettle in this team's short wildcard stage. Another compelling argument to give XTCN a slot is that the region of SEA performed quite well at TI6, with a top 8, top 6, and top 4 finish, and it would feel kind of shallow to only give SEA a single invite to the major. Out of all of the SEA teams left after Fnatic, this team seems the most deserving of that extra invite slot. Disregard their performance in the Shanghai Open, from what I've heard they played that with awful ping from SEA to China.
EHome - A top 6 finisher at TI6, this team has lost iceiceice and Fenrir and gained Garter and Sylar, both who have international credentials to spare. However, they have not been performing up to their typically high standards so far this season, and have been sorta of lost in the shuffle of the good Chinese teams just below Newbee and Wings. Their recent results make giving them a direct invite hard, but they have experience for days and have 3 top 6 TI finishers.
My Personal Thoughts
There are many philosophies that Valve might follow when giving direct invites, and they all have their merits. I'm of the mind that rewarding recent performances in the context of previous top performers at TI or majors is a good approach to take: you want to give incentives to teams that are on the bubble to play in LAN events to get themselves some exposure and win themselves into a direct invite, but you also want a healthy tournament scene for tier 2 teams to play in and earn some money. To accomplish this, having a small number of direct invites based on previous performance at majors or TI joined by a few new top performers is probably the best way to go, and I'm thankful that Valve so far has chosen this approach. With that in mind, here's what I would do if I were in charge of giving out invites:
4 Direct Invites: Wings, EG, DC, Newbee
8 Direct Invites: Wings, EG, DC, Newbee, Fnatic, OG, Team Secret, XTCN
I think, in both cases, these direct invites reward a combination of good recent play and good past results, and send the message to teams on the bubble like Liquid and EHome that you need to show something during the new season or you risk being left out of the major. This also balances regions pretty well, with 2 teams from each region to be joined by another 2 in qualifiers from each region. In my ideal world, I think this invite list achieves most of the goals I'd have in a healthy tournament scene.
Let me know what you guys think!