...so they are using Linux. That explains the kernel, what OS is it using (other than something from Oregan Networks)?
Some kind of BusyBox (very popular for PVRs etc?
Just saying "Linux" is not dreadfully important (a bit like saying "I run ntoskrnl"). Whatever the answer is a Linux-based system equal or beat a ntoskrnl based one. It all comes down to how well it has been designed and implemented.
For example, the V+ box is Linux based and simply dreadful to use. There again, Virgin have a long tradition of screwing up fairly decent hardware/software (SuperHub, anyone?)