Not in forever. I think the last video game I rented from BB mail was Lego Lord of the Rings (PS3), which was like a year and a half ago. Since then, like you said, does not seem to matter what I try and add. EVERYTHING is "medium demand" or higher.
Even the movie section, which has been good, in the last month or so, most everything on my queue is now "medium demand" or higher.
If it was not for the movie channels, I would have long since cancelled the service.
Personally, if you want to rent games, I would suggest going with GameFly. It's more expensive, and I'll be honest, shipping speeds leave something to be desired at times (especially in comparison to Netflix mail), but you'll at least get your games. Or Redbox, if you only care about new releases, and only rent a game or two a month. However, with Redbox, there's the issue of late fees, and definitely not as convenient as mail service.