When I first saw the iCade I immediately wanted one but then wondered what games might be compatible with the setup. Apple haven't made it easy so far to link in external controls to the iPad and despite the way the games industry has fallen over themselves to offer touchscreen offering over the past few years I'll always prefer using a traditional joystick/joypad. So imagine my delight when I read that the makers of iCade are offering to share their SDK, for free, with interested developers!
The second a major retro game is released with iCade support I'm likely to order one. Games like WWF Wrestlefest, Double Dragon, Street Fighter II, R-Type (to name a few) are all crying out for a good port with decent controls, so I'm praying the Capcom's/Namco's/Irem's of this world are watching and listening.