I went to the Time Life Website today and under The Odd Couple set is a message saying, "Due to greater than anticipated demand this set is backordered." It was previously backordered when first released this summer as well. This doesn't tell us specifics on how sales are going, but in light of that message, I think it's safe to assume, that sales are going well. I also noticed that they've dropped the price to $29.99.
With the Get Smart set, it says they will be available regular retail in the fall of 2007. Based on my experience with the Odd Couple set (price drop and additional disk offered w/retail purchase), I will wait until then to delve into Get Smart.