Avid announced a pair of iOS-compatible audio interfaces at NAB today. The Avid Fast Track Solo (US$179) and Fast Track Duo ($299) connect directly to the iPad to provide high-quality I/O for iOS apps that support recording, and also include licenses of Pro Tools Express for Mac and PC.
The Solo provides a mic preamp and instrument input, while the Duo (image at top of post) includes dual mic preamps/instrument inputs as well as line-level inputs. The Fast Track line is designed for mobile and studio applications, and does not require an iPad Camera Connection kit to attach to an iPad.
More information about the Fast Track Solo and Duo can be found on Avid's website and in the press release below.