I'm writing this with Typepad's iPhone blogging app. It seems to work well enough but it has a number of short comings which means it would only be useful under very limited circumstances.
The most obvious difficulty is with writing anything substantial on the iPhone's keyboard. Just getting a sentence right on the touch keyboard is a challenge. Writing paragraphs does not seem practical at all. The writing ends up lagging too far behind the thought process. The keyboard is workable for short things but definitely not for anything lengthy.
Shorter blog posts tend to be link blogging, but it's not possible make links on the iPhone. There's no option in the Typepad blogging app, probably because the iPhone doesn't allow copying & pasting.
So I can see iPhone being useful for photo blogging, for those people who are brave enough to rely on the iPhone's rather limited camera. It would also be useful for writing short posts which don't need links. But those sort of posts seem more appropriate for micro-blogging applications like Twitter.
I haven't forgotten about the rest of ALLA conference. I was hoping to get most of that finished last weekend, but unfortunately I've caught a nasty cold which I'm still dealing with. There is something wrong about going through all this when it's not winter.