BSN details why AMD is phasing out the 45nm Phenom II in favor of 32nm Bulldozer.
Since all their 45nm and 32nm are produced in the same Fab 1 in Dresden, there are tradeoffs to be made that ultimately affect both lines adversely. AMD has recounted repeatedly that they don't put up with the current situation anymore. We can only assume that the phase-out of the 45nm product lines may be one of the consequences of those manufacturing struggles. After all, especially Llano is in high demand which AMD struggles hard to meet. On top of that, there is need for additional 32nm capacity once Trinity enters volume production. Trinity is said to be launched early in 2012.