Since you can't yet copy and paste on iPhone (necessary for getting links into blog posts, in my opinion), I think the new Prologue theme released by WordPress is a great interface for iPhone blogging. To me, the Twitter-like interface of Prologue encourages short, twitter-style updates. Even if/when iPhone does get copy and paste functions, a short blog can be a great complement to your existing blog.
Furthermore, with the growing awareness of the need for Data Portability, I'd like to use Prologue to keep my status updates on my own domain, and feed them to Twitter using RSS. This might even reduce some of the load that seems to cause all those timeout errors I see multiple times a day from Twitterrific.
In related news, Chris Brogan suggests that Prologue is a step in the right direction toward a distributed, behind-the-firewall version of Twitter. He suggests that it may be very attractive for enterprises:
I think it's a great implementation for short messages like status and the like inside the firewall. I think it's a great step in that direction, and as WordPress has tons of other extensions and hacks, it's the kind of thing you can imagine getting to the other missing parts of Twitter.
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