I think tag entry UX is pitiful in Elgg right now. We of course need to add help text to let users know they're separated by commas (why are we assuming they would know this??), but I'm much more happy with the style of tag entry used by Delicious and other sites.

XOXCO has a jQuery plugin that implements this UI and I've integrated it in this plugin (code repo has latest). I've not evaluated this on mobile devices, but it's been much nicer on desktops and I'd like Elgg to have something like this in core for 1.9.

Thoughts? How are most of you dealing with tag entry usability?

(P.S. Please keep tag autocompletion in a separate topic. That requires much more/bigger decisions and a spec. E.g. do user A's tags autocomplete for user B? If not, why not, and always or sometimes? What if users enter offensive tags? etc.)