Well all engines with OpenGL base should work fine on Linux, best natively but wine shows also very good performance when you test id games with it. Saily many new engines are Direct 3D only and wine does not provide max speed with those. UT3 for example was the first UT game without OpenGL renderer which leads to performance problems.
Wow. Those screenshots look amazing.
I can't wait for the release. Hopefully we'll start seeing people adopting this engine. It'd be great to be able to show up my Windows-using friends when it comes to gaming graphics.
Okay, well, I couldn't with my current hardware, but someone could!