Whether to get a dual or quad core entirely depends on what you are going to be doing. I do a lot of running servers (especially at LANs ), encoding, video editing etc so it is definitely worth it for me. If you are into gaming then getting a dual core is probably the best idea.

HOWEVER this all depends on whether you are going to be overclocking or not. If you are going to be overclocking a quad core like I have, then you will find that it is as good as, if not better, than a dual core when it comes to gaming. However, there are the cases where you may be able to overclock a dual core more than a quad simply because of the heat output, so you will be better in games....you can see how this goes in circles !!