Hey Scott,
I did try catching up with you via Skype last night (your time) around 9.30, but you were prob working.
I have used it with the Line 6 Midi Mobiliser, using the Line 6 free Midi app. It's pretty basic and I would not really recommend it. BUt it confirms midi is definitely happening on the iPad.
I also have the Apple camera dongle (with the USB port) but I, along with many, many others am awaiting an app that starts utilising the Apple midi API's inbuilt into iOS 4.2.
I have connected my Edirol UM1-SX midi interface and it powers up fine, although with no actual app, I cannot go any further.
There are a couple of app designers looking at working with the camera/usb dongle. One has even bought it and is working on it.
Music Reader has now started the hunt for a developer to write into ITS iPad app, API midi support too.
Dennis