I never bought any of Criterion's DVDs but do have 10 Criterion LDs. These are Arsenic and Old Lace, Blade Runner, Close Encounters of the Third Kind, Diva, Howards End, Night of the Hunter, North By Northwest, The Third Man, Tootsie and 2001.
Looking at that list it seems that studios that originally released major movies are doing their own BDs: Blade Runner, Close Encounters of the Third Kind and 2001. It also seems probable that the original studio will release North By Northwest on BD and also most likely Tootsie at some point.
This essentially leaves Criterion with titles that none of the studios want to do, which I guess is what happened to Criterion and their DVD production. This, I'm sure translates into low sales which doesn't give them the resources to release a lot of titles quickly, instead it's going to be a slow dribble. I'm just thankful that they released The Third Man even though it was late.