Tumblr on the iPhone
I wish there was a good way to post links and pictures. Since I spend most of my commute to and from work checking out twitter, facebook, feeds an blogs, some kind of method à-la share bookmarklet they have for browsers would be sweet.
The situation will probably improve with copy-paste. Or a Tumblr app that has access to internet history in Safari and a built in browser (where you could say tap on an image to share) would be quite nice.