There's a new "planetary gromorphology image of the month" posted at the International Association of Geomorphologists' Planetary Geomorphology Working Group page, and it's a cool post about the shapes of the river networks on Titan.
Wow, this is a cool paper. Here's the gist: the Cassini RADAR team has spotted some river channels on Titan that shine so brightly in radar images, there must be something special going on to explain that brightness.
The Cassini imaging team has released an image containing a feature unlike any other that they have seen on Titan. The very dark color, curvaceous outline, and sharp edge of the feature have led them to the conclusion that it could well be the long-theorized but never-before-seen body of liquid hydrocarbons on the surface of Titan.