I have a site using the funky timeline javascript from the MIT.
SIMILE Timeline Documentation
The timeline is great, but tonight as I shipped a new build of my app to the server I was clicking ont he pages and noticed the timeline was broken, I'd not changed the code so this I wasn't expecting...
Basically what's happened is the server hosting all the Javascript has gone offline - not so good for idiots like me who have gone and just included the JS files remotely - my app is being crippled by this outage of someone else's server, that's not a position I should ever allow myself to get into.
So - if you do plan to use third party content inside your apps be they maps or timelines or even Flickr feeds, make sure you can rely on their stability or host all the content yourself because if you dont you'll get burnt like I have tonight.
It's a valuable lesson to learn.
This is even more interesting when I think about the YUI-EXT framework form Yahoo when they state one of the benefits is that it's centrally hosted so clients will only have to download it once, their servers may not go down but "yahoo.com" could be blocked on a firewall or there could be other routing issues.
Blergh - I feel so stupid for not having hosted the Timeline files myself - I now can't even get them from the server as that's on the same machine as the documentation and script files! :-(
That's a real benefit of Atlas and other such frameworks - your site generates the script out, it's not externally linked to - a massive benefit.
Edit - As I published this piece the site came back up and I greedily downloaded all the source code.