YUI or Yahoo UI library is now freely hosted by Yahoo. I think this is a good idea, and I would personaly use the service myself. But this brings up one problem that I've been noticing why my blog itself.
Having too many components of a web page placed on a separate server slows the loading of the page. Further, if a third party service goes down, your page goes into an endless loading cycle, or is not displayed properly. Just the other day, delicious was having problems, and the recent links section in the sidebar was not loading. It was a problem.
Here is why I've been thinking about this problem.