Delighted with my new toy, an Apple Macbook Pro, 2.4GHz dual core, 2GB, 200GB. But the wireless network speed was bothering me. I was getting ping times of between 20 and 50ms between the laptop and the base station, a DLINK 604+. Tried a bunch of stuff over a couple of hours, eventually got to the stage of systematically going through all the options I could see. Hit the nail on the head by turning off the "turbo" option in the wireless settings on the router. No idea what this does (actually reminds me of the old IBM AT turbo button), but the ping times immediately droped down to 1-2ms.
An other odd thing is that this was never a problem with the iBook.