The original games convention in Leipzig has basically split in two as I understand it.
First there's the [url=http://www.gamesconvention.com/:1i4edh2j]Games Convention Online[/url:1i4edh2j] held in Leipzig and pretty much the remnant of the Leipzig games convention of previous years. That one has already come and gone earlier this month without much notice.
Then there's [url=http://www.gamescom-cologne.com/:1i4edh2j]GamesCom[/url:1i4edh2j] which is held in Cologne and will be in little over a week. This one is expected to be a big event much like E3 and the old Leipzig games convention. This is one that one might expect a fair bit of news from. For instance, BioWare is showing off some Star Wars: The Old Republic gameplay (same stuff as they showed at E3, but now not behind closed doors).
And then there's [url=http://www.blizzard.com/blizzcon/?rhtml=y:1i4edh2j]BlizzCon[/url:1i4edh2j], which is held pretty much at the same time as GamesCom and is Blizzard's very own little conference (with as such pretty much only Blizzard games). From this one might expect some WoW, some Starcraft 2, some Diablo 3 (probably a new class revealed) and [i:1i4edh2j]maybe[/i:1i4edh2j] a little on some unannounced things (like the new MMO they're working on).
Finally there are a number of other converences like [url=http://www.paxsite.com/:1i4edh2j]PAX[/url:1i4edh2j] (Penny Arcade Expo) early September and [url=http://expo.eurogamer.net/:1i4edh2j]Eurogamer Expo[/url:1i4edh2j] at the end of October (and probably a number of others I've missed or don't know about). There's a reason why this time is called convention season.
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