Hi- I got my first mac and had a horrendous time tryign to figure out why my internet was abysmal. I mean- it was far worse than my six year old pc. i bought an airport extreme (needed a new router anyway) but that did nto fix the problem. My wife's ibook had problems after leopard, and her desktop also had network issues- but it was not updated to lepard- only to 10.4.1 or whatever the latest Tiger was. So i did some searching and i wanted to post the solution here, as this seems to be frustrating the heck out out of a lot of people: go in to your settings, click network, and click advanced. Click on DNS, and add in the DNS ips 22.214.171.124 and 126.96.36.199 It fixed the problems for me.