Alesis Studio Dock aka iO Pro (per Alesis' site)
Game-changer? Could be! Purportedly solving the number one complaint of most iPad musicians - iO Pro adds "real" i/o to the iPad, providing a traditional hardware MIDI interface, USB/MIDI, 2 XLR inputs (w/ 48v phantom power on one channel), R+L 1/4" outputs, headphones out, a footswitch jack, trim pots in all the right places, an impedance switch on one input, and even composite Video out! Everything but, well, the iPad...
List is $399 but Sweetwater's catalog shows it at $199. Add an iPad (~$500 depending on your prefs) and this could be an affordable and flexible alternative for laptop musicians, or for musicians currently using the iPad primarily as a dumb controller for existing computer-based music apps.
Of course, much will depend on the availability and affordability of IPAD apps that can take advantage of these added i/o options. And it remains to be seen whether the quality of the audio produced by the combo actually turns out to be "Pro". Can't wait to get my hands on one!
More reading:
CreateDigitalMusic iPad app rundown
Other CDM articles on iPad apps
An in-depth look at io Dock @ MATRIXSYNTH