I'd say Intel still have the upper hand. Overall the quad-core will be better for your needs. The E8500 will be better for gaming though.
If you get a good cooler (e.g. click here), the Q6600 can be easily overclocked to 3Ghz (or more depending on your motherboard, RAM, PSU) for an added boost, which should help in gaming too.
Btw, the Q6600 is a bit cheaper (~£113 incl del) at Aria click here. G