Just an idea, with Christmas coming in just over two weeks, why not decorate the place for the event? We could change the lemmings logo at the top to the Holiday Lemmings one for example, and the male/female lemmings could be walking in front of a Christmas tree! And the summer lemming could be in a Santa suit with a present in his hand.
Just suggestions, but it would bring the Christmas love into the forum. I would even edit the current sprites if wanted, I can do a little pixel art.