There is a limit on how backward compatible things are. Rumor is, Bulldozer is based on totally new architecture so I doubt it will fit on any current mobo. Look at K7 (socket A) and K8 (start with socket 754), and the current K10 is just a beefed up K8

Most people fail to see that not much game/software really needs four core, let alone six. Most software/games still favors high clocked of fewer cores rather than slower speed with more cores, which is why most of the time the Phenom II X4 wins.

Don't expect miracles, it still based on K10 'Stars' architecture, with a couple more cores with dynamic boost, no other architectural difference. Until AMD release new architecture, Intel will continue to dominate the higher end segment