Photobucket is very weird that way! I switched to using LJ's pic hosting for layouts and such because of it, despite LJ's crappy (or should I say nonexistent) interface - I noticed that if I uploaded the images to Photobucket, they'd load fine the first time or three, and then begin to horribly degrade despite being stored properly on the service itself. Not sure if it's the same problem you're having, but ... yeah. Photobucket is just bizarre sometimes.

mmm..it might be. Especially since I didn't notice the horrid quality when I posted the pics the first time. What a weird way to do it all, right?

Soem people here said if you save the icons as pnd there is no such problem.