Tobold wants to know what's going to happen at Blizzcon. I've looked at this question previously and some of my calls are looking pretty good. It looks like we're going to see Patch 3.0 go live on Tuesday. Blizzard kind of let that cat out of the bag by saying that the arena season would end, but I'm sure they'll announce it like breaking news at the keynote anyway. Blizzard has also hinted that we will finally hear something about the planned ability to allow players to have two talent specs. Beyond that?
We've already got a fair chunk of info about stuff that's to be included in the post-Wrath content patch. Notably, account-wide achievements and most likely the dual-spec thing will be going in. With a month left to go before the expansion's retail launch, I'm not sure that Blizzard is going to WANT to announce any more major features that won't be ready in time, for fear of making the expansion look unfinished. I expect very very little new information on the WoW front.
Playable on the show floor, with the unveiling (but not necessarily playable debut) of a third playable class.
Tobold thinks that a release timeline for SC II would be "lame". I expect Blizzard to unveil beta testing at best. Does that make Blizzard partially lame? ;)
Battle.net version 2.0
This may be the most likely area for big announcements, and perhaps even an unveil of the new interface and features. Blizzard has already announced that they will relaunch the service with Starcraft II, that they will move all games towards the Blizzard Account for logins, and that WoW's achievement system will be part of a broader "Blizzard level" system that tracks achievements across multiple Blizzard games (to include SC II and DIII). This is also the one area where they can spin WoW-related announcements as "WoW will be updated to be comaptible with the new BNet" as opposed to "there are features for Wrath that won't be in for launch".
The Mystery Fourth Project?
Not this time.
My track record on these things has been mixed; I'm as likely to have all these things disproven by a leaked press release sometimes in the next 10 minutes as I am to get them all right. Still, I'm not expecting anything groundbreaking at this year's edition of Blizzcon. We'll see how I did come Sunday.