I tried to use Google's AJAX CDN (because I was thinking the same thing you are) and have been burnt several times because of it. Occasionally, it won't serve y

I tried to use Google's AJAX CDN (because I was thinking the same thing you are) and have been burnt several times because of it. Occasionally, it won't serve your js files, leaving users with an indefinite 'Waiting on ...' message or a partially rendered and broken page. It's fixed if they refresh. If you use your own server, at the least there's a connection already established and the JS files will be served. My suspicion is that Google is prioritizing other traffic, and the free AJAX CDN is low on the list of services that should work flawlessly.