Most of the high end video editing software is multi-threaded. So if you are running Adobe CS5 it does take advantage of all thread available to it. So going with a 2nd generation Intel® Core™ I7 2600k will give you your best performance in that software. The Intel Core™ I5 2500k will give you very good performance but not on par with the 2600k. So the best advice I can give you is to check with the software maker to see if they are multi-threaded and if so how many threads can they take advantage of?
Intel Enthusiast Team
I read that the i7 can lower the performance in some games. If this is true than should I go for the i52500k or will the i7 2600k be ok?