Correct me if I'm wrong, but the high speed of the CDN isn't the only (or even primary) benefit. In my opinion, browser caching is a much bigger plus. As soon as a user downloads one of these hosted libraries (by visiting a site that calls for it), their cache is primed for every other relying site they visit. Correct?<p>Assuming this is true, why would someone use the Google API Loader javascript call ("google.load") instead of linking to the file directly? Linking directly allows the browser to use its cache, while using google.load needs to make an external call to Google, bypassing a big benefit of the caching.
You need to be careful about user privacy with things like this. You're leaking user information to third party services, and you need to make this clear to your users, especially if you're dealing with anything that could be considered at all sensitive.
Is it really faster? I always assumed that the additional client side DNS lookup would eliminate the increased bandwidth advantage that the CDNs have. Anybody know if anyone has A/B tested this?
FYI Yahoo still maintain their own CDN for YUI which has additional features such as submodule selection, so you can roll a package that fits you, and we'll host it.<p>Disclaimer: I work for Y!
Google went down one day and all of these CDNs stopped working at our colo. We got over 50 calls of people complaining their sites were down. Turns out the sites were blocking on waiting for the javascript (timing out after a few minutes).<p>That is the only time it has happened, but this is what makes me fear being fully dependent on these CDNs. So be advised: add a fallback mechanism.
The caching aspect is one pro to using these services, but by using these CDN's, your exposure to failure is greatly increased. Instead of factoring in the risk that your own server or network may be unavailable or slow, you now need to account for 1, 2 or 3 other networks that you are grabbing files from.
Doesn't this prevent anyone from whitelisting your code in NoScript? As a user, how could I ever know that you've reviewed what the CDN is serving right now? ECMAScript sandboxes are not nearly good enough yet to run untrustworthy code.
I really need something like this for my CSS Frameworks. Fast DNS query resolving + gzip.<p>I think that Google and others(Microsoft,Yahoo) should give free access for more public libraries. So we can all benefit from that.
Thanks! Good to know, even if I may end up copying the files to my own server anyway.<p>Edit: I assume the plan is to keep this list updated with the latest version of each lib. (?)