For the last several months I've been noticing that My Yahoo has been extremely slow.  I think it's the banner ads that inhabit the top portion of that page that are slowing down.

For a refreshing change, try the new personalized home pages offered by Google:

http://www.google.com/ig

There isn't as much content available, but it's very fast.  And it will display your Gmail inbox right on the home page, in addition to your local weather, RSS feeds from Wired, Slash Dot, NY Times, and the BBC.  That'll do!