i think this phone is disappointing in a way. from previous series upgrades the step up from k750i to k800i was a major one but the k850i i think still needed a bit more time under development. all they have managed to do is create a phone with half it potential; rele they could have gone out of their to install many feature missing from todays line of camera phones such as a true mechanical shutter, optical zoom, better video recording quality and the list could go on. i know you can argue that k800i didnt have half the stuff im mentioning so why should the k850i go any further that it has to, but time has gone by and so has the need for THAT extra technology. if SE rele put their resources into the production of this phone they could have made a mobile history of the first true dual faced (purpose) phone.
i approve that k800i should carry the cybershot name as it was an landmark, a sort of industry standard by what all camera phones are measured by and showed the future of camera phones. frankly the k850i isnt the future that the k800i promised from one of the greatest mobile manufacturers. it seems like it was stuck together with parts from other developed phones and given a 5 Mpix camera just to try and combat the N95.
what SE has been good at in recent years is creating a phone that fully fulfills its purpose in the market.
basically what i think the k850i adds up to -K850i=k800i +5mpix camera, which isnt a bad thing just not the phone we were expecting.

sry if this post offends any one but this is just an opinion.