I doubt that Microsoft will release the next XBox in 2009 because they actually have a better piece of the market with the 360. To me the early release of the 360 felt like a desperate attempt to put the XBox into the back of everybody's mind--especially after they pretty much discontinued any support for the XBox so soon--and be the first company with HD gaming, and it looks like it worked (in US/EU anyway). Now if they jump the gun and release the next XBox in 2009 it is going to have that same feel and people will probably criticize them for having a laughably short console cycle like they did last time around.
I just don't think that Microsoft stands to gain that much much by releasing in 2009 as opposed to 2010 or even 2011, and I know that personally I would be disappointed if they did.
