Sigma - The release of their 3 x 15Mp Foveon sensor is pretty big. The Bayer versus Foveon debate will never be over - since with high resolution the Bayer array with a single color recorded at each pixel location does a remarkable job of reconstructing color. However, this proves the Foveon is current and has some potential to offer high resolution, too. I just wish Sigma would make a body with a different lens mount. I don't see this making a huge impact in stock - too niche a product when limited to Sigma lenses.
Canon - While I use Canon I find their announcements this year sort of ho hum. The 60D is disappointing in that it loses some key features in the x0D line - like 3 custom functions, rear dial, microadjust and a flash sync port. That said, both it and the G12 have a fold out screen - a first for Canon. The 60D could be great for video, but as mainly photo guy I think I'll be pushed up in the lineup to the 7D for stock - playing into Canon's hands, I guess :) Nothing earth shattering in the photography dept, Canon seems to be focusing on the HD video segment right now.
Sony - Sony is doing some very interesting stuff. Before the show they announced their translucent mirror models with fast phase detection AF during video, and the sleeper hit of the show, in my opinion, is the release of a firmware update for the NEX to allow AF with A mount lenses. This makes Sony the only manufacturer with a very compact mirrorless option, APS-C and full frame cameras that share lenses. Sony seems like a great choice for the stock photographer, with the highest resolution bodies, good lens selection and innovation across the lineup.
Olympus - With an update to the E-3 (the E5 ) Olympus is keeping up with the Joneses, but just can't quite put it together. They have a great jpg engine and well regarded glass but with no sensor bigger than four thirds they just can't quite be taken seriously if high resolution and low noise are important to you - and for stock they are. There is lots to love about Olympus, but I just can't switch to a lineup with no larger sensor options, and seemingly no plans to move there.
Pentax - They updated their DSLR, but the bigger news is probably that their medium format option is now stated to go global. I'd think a few landscape photographer will jump at this one - weather sealed medium format? Sign up with Pentax!GH2 has doubled its AF sampling rate to 120 fps. The class leader of contrast AF, they are pushing others to compete. The 3D lens is cool - not sure if it will take off though.
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