@mrstickball,
Do you realise that there are no third party exclusives anymore this generation? You are talking about devs shifting from PS3 to Wii, while there are no PS3 third-party exclusive games to begin with.
To quote what Mark Rein said in that article "Not everyone predicts a big shift in spending, because PS3 and Xbox 360 share many titles and costs. Game companies who fail to commit enough money to PS3 risk losing business" So multiplatform game will be here to stay.
What you are saying about Microsoft may do stuff like timed exclusivity rights is true, but Sony can also do exclusivity rights, like you see Sony doing it with SEGA for games like Yakuza III, Valkyria Chronicles, and Tecmo's Quantum Theory. So what you're saying is really a moot point.







