I have a clean, out-of-the-box installation of Visual Studio 2012 Web Developer Express and for some reason the support for JavaScript (both jQuery, jQuery UI and
I included jquery-xxx.intellisense.js in JavaScript -> Intellisense -> Reference. It worked one time, but after I closed Visual Studio and restarted it, intellisense didn't work again.
But I accidentally hit menu Edit -> intellisense -> Refresh Remote References. It worked again.
Try that!