Simplicity
I don't think I'd have been as receptive to Posterous's slick user interface if I hadn't just read this post http://trenchant.org/daily/2009/9/8/ But, even before that, I'd decided that what I really wanted was a way to write blog posts that was as simple to use as Twitter. Twitter, after all, is where I expend most of my creative writing energy these days. So the idea of an almost completely frictionless blog posting tool was appealing. I'm a sucker for a nice bit of Helvetica though, so we'll see how this sticks beyond the first couple of days. I was enjoying Tumblr for a while there too until Tumblarity sucked the fun out of it.