I have to agree with CADharsis on this. Cycles is not production ready even if it is a wonderful addition to Blender. And to be honest I love the simplicity of the material editor in Thea, because the node sistem in Cycles is very powerful but it can become overpowering for a simple artist.
One thing I notice with using GPU with Cycles is that I can´t continue to work with my computer. The GPU is used to draw the screen and my video card is not very good, so my refresh rate on the screen is very bad. The solution is to bought a second GPU only for render, and keep this one for the display.
So, I'm not really sold on GPU.
I hope that when GPU arrives to Thea it will be a solid addition to a already stable platform.