From what I see ...
The PS2 and PS3 account for 17% of Activision-Blizzard's total revenue in 2008, by the end of 2010 the PS2 portion of that revenue will fall to (essentially) 0%, which means that for Sony's consoles to retain their current share of Activision Blizzard's total revenue the PS3 will have to double its sales of Activision Blizzard software over the next 2 years. When you factor in development costs and how the PS2 sales would be mostly games that were released in previous years (and almost all revenue generated would be profit) the PS3 will have to more than double its current sales of Activision Blizzard software to maintain their share of total profit.
Now, how many people think that Sony will be able to sell enough hardware to boost Activision Blizzard's sales to over double its current level by the end of 2010 unless they reduce the price of the console immediately? With the exception of a few fanboys I don't expect anyone does ...
What this means is that Activision Blizzard's threat is actually fairly legitimate being that the development costs associated with porting XBox 360 games to the PS3 are probably higher than the costs associated with creating (lower budget) Wii games which could generate greater profits for Activision Blizzard; and the consequence of dropping Sony with how unimportant the PS2 is becomming, and the PS3 and PSP already are, is pretty minimal.
