We have it and love it. We watch lots of independent films (the annual Waterfront Film Festival here in Saugatuck every year spoils the heck out of us) and tons of documentaries, so the selection is a lot better than the video stores. Turnaround time is fast for us, and discs always play fine for us. It's nice, too, because you can put stuff on your hold list that is still in theatres, so when it becomes available on DVD you're already on the list. For us, it's money well spent, but we watch tons of movies and stuff, so it's been great.
We were out with a group of friends and after a few rounds started talking about how much $$$ could be made in doing a Netflix service, but for porn instead of regular movies. We were all fired up about it, and were going to name the service "NetCl$%s" (part of the female anatomy that rhymes with flix, more or less). But, when we got home we found that many, many entrepreneurs had beat us to the punch.
Anyway, it's great. Evidently, for the first year, the Blockbuster copy of this service is a few bucks cheaper per month, but then it jumps up quite a bit afterward.
We've been doing 3-4 month Netflix gift certificates for gifts lately and people really love it.