April showers have yielded us a Back Compat update The latest backwards compatibility update is now available over Xbox Live (or will be very soon.) This free update brings the complete list of original Xbox games that you can play on your Xbox 360 to over 300. Remember, your original Xbox games will look better than ever on Xbox 360 running in 720p and 1080i with anti-aliasing. You can also play cross-platform between Xbox 360 and the original Xbox over Xbox Live.
Here is the updated list with new additions for April '07:
Breakdown Call of Duty 2: Big Red One Call of Duty 3 Cars Crash Bandicoot 5: Wrath of Cortex Daisenryaku VII FIFA Soccer 2007 Full Spectrum Warrior Guilty Gear Isuka Jet Set Radio Future King of Fighters 2002 King of Fighters: Neowave Mad Dash Racing (Japan only) Mech Assault 2 Mercenaries: Playground of Destruction Oddworld Munch's Oddysee Panzer Dragoon Orta Star Wars: Republic Commando Street Fighter Anniversary Collection Ultra Bust a Move /ULTRA Pazzle Bobble Unreal Championship 2