While PS3 users are happy to get the occasional PS1 title repackaged in downloadable format, the 360 doesn't merely get direct ports, but genuinely enhanced versions of classic fan favorites: Doom, Marathon, Prince of Persia, Street Fighter, and now even Rez! And all of these game have upgraded textures and graphics, improved frame rates, a variety of multiplayer options, etc.
Microsoft provides attractive hobbyist oriented XNA dev kits with options for 360 distribution.
The 360 seems to get many third party titles much earlier than the PS3. This includes traditionally PlayStation franchises such as Ace Combat and Katamari, which are rumored to come out for the PS3 after a 360 exclusivity period. Even titles such as GRAW 2, which the devs claim was designed from the very beginning to provide full PS3 support, still come out a solid five months earlier on the 360.