Would be GREAT if they, or someone, could colorize the b/w ending footage. BUT WAIT!! A rumor from deep within Warner Bros perhaps has this on the cards. They are known to be doing a 2-disc Little Shop, and have said they "want to do it right". From another source, I have heard mention of color elements.
Seemless branching to pick a "happy" or "sad/original" ending would be cool, and it's something WB is playing with on the new Final Destination flick on DVD, but as far as I know right now, it's just an extra...