Hi, I just encountered this issue about 2 days ago on my 2009 2.66 GHz MacBook Pro 15. When I am connected to a wireless network my internet goes REALLY slow (30 Mbps wired vs 2 Mbps wi-fi), I cant even watch a youtube video anymore without waiting 5 minutes. My wi-fi signal is full and I am maybe about 15 ft away from my router. I have tried reinstalling OSX and restoring my router but nothing has helped. I also have a Macbook Air running on the same network and connected to the same Wi-Fi and my speed is normal (around 30 Mbps) so I know its not an issue with my router. All my computers are running the latest snow leopard and needless to say, I have zero programs or anything else running on the macbook pro because its on a fresh install of OSX. And just to be clear all these issues occur only when I am in Wi-Fi on the 15 inch, wired works normal on the 15 inch. Any Help is appreciated thanks.