Botgirl has a nice intro to Twinity for SL residents. One highlight from her review:

Although they’ve made a clear effort to simplify their interface, I didn’t find it especially intuitive. That said, after a few hours of effort, I was able to pay more attention to experiencing the world than figuring out how to operate within it.

…

Now here’s the fun part: You can clone your Second Life avatar by importing a few images.

…

The mirror is especially cool.

Also, the PÖNKblog has some info you might want to check out, and a thought on the avatar created using Twinity’s face generation tool with some SL avatar screenshots.

In a way it looks like a mix of my SL-avatar and my RL-self, which seems fair, as the Twinity-Berlin looks like a mix of SL and RL, too!

Thanks to both of you for your posts!