Along with Erica Sadun, I had some trouble connecting my shining new iPad to an Apple Bluetooth wireless keyboard. Eventually we both got it sorted out, but there are a few things that you do need to know. My problem was that although I could connect easily to an older BT keyboard, I could not pair with the one that came with my new iMac. My solution was found in this video that showed me that I had to totally get my iMac to forget the keyboard before it could be paired to another device.
Obvious? Well maybe to many, but not to me. This video by huskermania walks you through it simply and elegantly.