As with all things Posterous, it’s designed with simplicity and minimalism in mind. The release also features a few nice touches for the iPhone, specifically “users can swipe left and right to go back and forth between pages. On a blog list page, swiping goes to the next and previous list of blog entries. On a blog post page, swiping goes to the next and previous blog post.”
Unlike Tumblr’s you can’t current customize the mobile version to match your main sites design which is bound to disappoint some users. Commenting also appears to be a missing feature.
Check this out now by visiting any Posterous site on your mobile.
Let the Tumblr vs Posterous battle continue. It really is a pleasure to watch.