Could somebody tell me how many cores Vue uses to render and for working in the application?
Will Vue 7 use more cores to render?

Thanks

Vue 6 infinite uses as many cores as you have.  Dunno about other versions though.
Note that Radiosity calculation amongst other things only uses one core at the moment

Infinite & sTream use as many cores as you can put in your machine. Other versions are limited to 2.
As Frank said, some features are not multithreaded, radiosity & caustics preparations, and panoramic renders come to my mind.

Thanks. That's very good news!

 Not all functions of vue use all the cores though.  Fortunately, rendering does.  However, populating eco-systems doesn't (this is where I often get tripped on the 10-minute beach ball).

TIP - For those without lots of cores, carefully adjusted render settings can get you almost as much additional mileage efficiency as lots of CPU cores.  Model without textures and atmospheres, test small sizes, and nudge render quality settings up slowly as you go.