Encoding yes, you can encode for compressor with a Qmaster Node (Included with FCS) and add as many machines as you like. We have 6 Dual 1.8's for Compressor encoding, was very easy to setup to a 8 port Gig-E Box and an X-RAID.
I don't know of a way to do rendering of your Final Cut Timeline or anything like that, I imagine it might be possible, ill ask around if that is what you are looking for.