Perfecting the Robotron gameplay... In space... with neon... just what an arcade game should be
It's also integrated into PGR3 in a very creative way: when you walk around your 3D garage admiring your cars, you see two arcade games against one of the walls (Geometry Wars 1 and 2) - you walk up to the machine and it asks if you want to launch the game in XBox Live Arcade. This works almost perfectly (I'd like to see it go BACK to the garage when done with the arcade game instead of launching PGR3 normally) and is a great example of how elements of the 360 just work together.