Do you know of a tab widget that has built-in drag+drop reordering? I'm building an editor-like interface and want to allow the user to reorder their tabs.
So far I've been using ExtJS with a community plugin, but it's buggy and usually needs updating with every new ExtJS release.
There are attempts to make jquery tabs drag and drop able. While it is not drag and dropable out of the box you could make them yourself in jquery-ui.
Here are some resources that tried it: Resource 1 Resource 2
There's a draggable tab widget based on YUI lib just for that.
If you're not concerned about adding another javascript lib to your application, I think it's an interesting alternative. You can even drag and drop tabs from other containers (I didn't see this feature on your ExtJS plugin by the way).
Is something like this what you're looking for?
I'd definitely use jQuery and jQuery UI as a base if I was trying to do what you are. The solid support structure and wealth of tutorials around jQuery is unbeatable!
Of course this is if you don't mind the weight of another javascript framework or having to recode some of your interface.
On a slight tangent, if you want your interface to remember a user's preferences you'll need a server-side language. Alternatively, use the jQuery cookie plugin to store preferences between page loads.