I can recommend System76 if you go the Ubuntu route. My desktop at home is a System76 Leopard Extreme that I dual boot Ubuntu / Windows, and prior to getting my MBP I was using a Pangolin Performance laptop.

Since getting a MBP I can say that I do prefer OSX to Ubuntu, but I'm a Ruby/Rails dev surrounded by other Apple guys using Textmate so it's the path of least resistance for me for sure.