I recently used Slick a bit in combination with Play.

On one hand I was really impressed by its capabilities, on the other hand the documentation is unfortunately lacking...

I think Slick has great potential and hope that typesafe brings the documentation onto a quality level similar to Play. If you want to try it out today and get stuck, after some time I found it quicker to look at their test cases first before googling, much more info there than in the docu and example projects.