Then why such low performance in an almost empty level? I mean, the desert level has nothing except a terrain, scattersky and advanced lighting. This just does not give me much confidence in how it might behave in a bigger level with more art, and probably also other stuff like AI going on. Don't get me wrong , I am not bashing T3D.
The idea is, effectively, that with Deferred Lighting(the older method), it had less up-front cost in rendering a scene, but didn't scale as well as more and more and more stuff was added into it.
For deferred shading, there's a higher up-front render cost to render a scene, but as more things are rendered in the scene, it scales better. Which is why a nearly empty level doesn't perfom as well compared to the older builds. However, as Timmy said, if compared, you should see better performance in a fully loaded level.
Try taking the pacific demo package and tossing it in there and seeing how it scales comparitively. http://ghc-games.com/SC/Pacific_Package.rar
Are there plans to make T3D support multicore processors better?
Yep, this is definitely the plan. I've already done some testing at threading the renderer itself, and we've also been looking at running a thread for the client and one for the server(as T3D always has both, even in singleplayer). This would effectively get us a thread for rendering, and then the server-side stuff, like physics and AI would be in a different one. This would help a ton with performance.