Posterous finally adds themes to make your blog look less boring

Posterous just announced an exciting-if-inevitable addition to its simple blogging service — themes that let users customize the look of their blogs.

The San Francisco startup has been around for a year now. Posterous’ main draw is its simplicity (first-time users don’t even have to create an account to publish their first post; they can just send an email), and recent improvements include better support for video viewed on mobile phones. Still, as the site has grown, it’s seemed sillier and sillier that everyone was stuck with the same boring brown background.

Well, Posterous finally announced that it’s letting you choose from looks for your blog. Posterous provides five themes for now. That’s not a lot, but the company says more are coming soon. Plus, each theme can be further customized with colors of your choosing and an image at the top. Users can even use CSS and HTML to create their own themes.

That last feature allows Posterous to build on the work of more-established competitor Tumblr — themes created for Tumblr now work in Posterous too.

Posterous was incubated by Y Combinator (which has a Posterous blog, by the way), has raised $725,000, and had 4.4 million unique visitors last month, according to Quantcast.