if you post a thread like this you don't need one
some 3d work, modelling, rendering, video work yes a quad core will do you great and spending lots of money to increase productivity is worth it, for work. not a single game makes worthwhile use of it. sup commander uses them but we're talking max fps 39 with a dual core and 40 with a quad core, who cares.
alan wake will possibly use a quad core well. the pre-release hype says it will use a quad core, but that doesn't really mean anything. marketing words and new things games can use all sound pretty and make people think they are advanced(though alan wake looks sweet), but USE and NEED are so so far removed from one another that its simply a wait and see situation as to when we'll really see improvements with quad cores in gaming. there are some beefy looking games on the way, but you can have beefy and extremely efficient, and crap and incredibly inefficient.
definately, at minimum, wait for the price cuts, but remember a possibly big reason for the honestly quite ridiculous price cuts to the Q6600 could be to clear out a backlog of kentsfields for upcoming penryn's. now at first glace i don't think anyone will really notice a huge difference between the cpu's. the only real improvement is SSE4 which is pretty decent, but only if the apps use SSE4 which could take a long time other than a few early encoding applications.
personally i think the Q6600 will be a VERY good chip for very good value once the price is cut and will be a great upgrade for the future games coming in the next year.