Las Vegas - Is KA dark during the month of December?

And if so, where can we go to get discount tickets to other shows?

All you have to do is go to MGMGrand.com, look under the entertainment section, select KA, and then check the schedule to see whether or not it's playing. As far as discounts go, I'll be in Vegas in December as well and I really haven't come across any good promotions for shows like what we had in the summer with the $50 Cirque tix. Thankfully, hotels are so cheap that it's offsetting the difference and then some.

And if so, where can we go to get discount tickets to other shows?

No, KA is not dark during December.
http://shop.lasvegas.com/shows/showtimes2.jsp?show=727&start=200712&lang=en&src=tix&seats=2&display=#select_tickets

For Vegas show discounts, check TravelZoo (http://shows.travelzoo.com/las-vegas-shows/) periodically or go to one of the half-price ticket outlets the day of.

Use this link to search for what shows are available during specific dates you are in Vegas. http://www.lvol.com/lvoleg/search.html

Thank you to all!