The NDA is still in effect as I write this so..[REDACTED] etc., etc.. but I think it's safe to say that I absolutely love programming for the iPhone. One might even go so far as to say it has restored a sense of childlike wonder to my life. For the first time, I have a mobile phone that I can make do (almost) anything I want it to do.
I can also tell you that I've seen and used some other iPhone applications and, well, prepare to be blown away on Friday. You're going to see some incredible things, that much is certain.
At some point after Friday, I hope to write up a post-mortem on developing Exposure (and FlickrExport Touch, which I'm still working on). Oh, and did I mention that, in the middle of all this, I finally switched to Git, nearly a year since I first considered it?