It has 4 physical processors and in programs which support hyper threading there are 4 more virtual ones however these are not as fast as the 4 physical ones.
not a lot of games are multithreaded but some programs are. Programs geared towards rendering and that type of thing will eat all the cores you have :]
but as stated above, it's 4 physical cores with 2 threads each making it like 8 virtual cores or something like that