I want to know becuase i want to buy the 2.4 but i know that it will be cheaper as soon as the newest is released. I heard october? and that the 2.4 is actually already being discontinued?
No-one knows. Apple traditionally works to roughly a 6 monthly refresh cycle for the MBs and MBPs but sometimes it can be as long as 9 months or as low as 3-4.
The new Intel chips have only just been announced, so don't expect them immediately, although we know that Apple is working on new designs that more resemble the MacBook Air. That said, they will not be radically different.
No-ones knows exactly when; however there is a good chance there will be a revision by October but any speed increases over the current version will be modest.
Suggestion: You might want to do a search next time. The "should I buy now or later" type threads are the most often posted topic here. Hope you find your answer!
I would like to point out that I am utterly bewildered as to how many people post threads like this. We didn't know when then last person posted the exact same question and we never will. Apple will announce it eventually. For now the answer is always the same. Buy now if you need it now, buy later otherwise.