Greenleaves hit it.
Seriously, though, I wonder how many gays went and registered domains after reading this thread. I think if someone wants to market this effectively, it's best to drop the term "mangagement ring." It looks too much like "management ring." Since that's pretty much what it is, that's the last thing a marketer should call it. The best way to market this is to come up with a less offensive name (or... gasp... something positive), reg a name, blast up the social media, and try to take control of the language. Buyers won't want to run around saying their girl got them a "management ring," but I bet they'll use a cooler term if given one. On top of that, I'd say girls will have an easier time selling their guy on the idea.
Now I feel a little slimy for contributing to this idea, but whatever.