
Often you want receive more information, with your autofill widget POST data. Currently all you get is a string, optional with comma separated values.
What yo really want to send along in a POST, is at least a unique ID, such as the node ID, or user ID.
For that you need a better interface, IMO. Comma separated values in a single textarea is just fine for Tagging, but anything beyond that requires an interface that allows you to simply add/remove or change what you have found.
This mock-up is a proposal for that. I designed it for Clipper, which wants to find parent nodes.
It downgrades fine (see the bottom set, for how non-JS versions will behave.