One of the (few) things I'd like to see altered in future WP versions is the ability to have the post title/slug updated on the fly whenever the title is changed. I may want to rename my 'zomg Star Trek review!!!1!' to 'Reviewed: Star Trek', but once I have done that I need to manually update the title field myself, which involves clicky and typing.
Instead, how about having the title automatically update, whenever you make the change, or even just an 'update' button next to the existing 'save' and 'cancel' buttons/links. Saves a couple of seconds that I'd just prefer not to waste.