The development branch of WordPress now bundles Prototype 1.5. A number of themes and plugins have been bundling Prototype, so we decided to make it available out-of-the-box. We also use it internally for the new autosave feature.
The development branch also has a nifty script loader from mdawaffe that makes including JS in a cacheable way very easy. For example, if you want to use Prototype in your theme, include it like so:
wp_enqueue_script('prototype');
The script loader works for themes as long as this patch is applied 🙂
Applied.
This is great. I hope more AJAX plugins make use of this. I have 3 or 4 AJAX plugins now, all of which use slightly different versions of prototype or prototype.lite or moo.fx, so I’m forced to load all of them to avoid breaking the plugins.