Pros Fairly inexpensive, compared to the i7, overclocks very well, speedy.
Cons Can't think of any. It doesn't have some of the media functions of the newer i7. Only four threads instead of eight. Less onboard cache, no visualization tech built in.
Summary I'm a gamer, and I bought this because I do more gaming than media. This cpu is 3.3GHz but will overclock to 4.5GHz (at least mine will) with a decent cooler. It really flies and you get great bang for the buck. If you're more into media encoding, I would recommend the i7.
I upgraded from a Core 2 Quad at 3.3GHZ (overclocked) to this i5 2500k at 4.5GHz (overclocked) and the difference is night and day. My old CPU was bottlenecking on BF3 (even with 2 x HD6970 in crossfire), and now there's no problem at all.