Easy way to manage Thumbnails in WPMU

Hi folks,

I wonder how do you manage users that want to display thumbnails with their posts ?

My users want this : upload and image. And wOOsh, a thumbnail appears on the left of their post' excerpt.

The best solutions I've found so far still require the user to add himself a key/value to each post (key = 'thumb' + value = 'url').

Is there a better way to do that ? (I mean an easier/faster way for users)

PS: I've found a plugin from Justin Tadlock http://justintadlock.com/archives/2008/05/27/get-the-image-wordpress-plugin - have you tested it ? On WPMU should it be on plugins dir or mu-plugins ?