When I had some credits on amazon I was looking through the movies and a few of them had a note saying that if you purchase this movie you have to download it to your computer by a certain time because it would no longer be available in the library. Glad to hear you haven't had those issues on vudu.
I think drm is ok at times as long as its implemented properly. I wouldn't put up with it on music though. I use amazon for all my music purchases and its stored in the cloud for free and I can also download a drm free copy anytime I want. I purchase all my games through steam. It would be interesting to have a single services for all your online video purchases. I wonder can you at least store a copy offline and still view if your not connected to the internet? I think some game services allow you to do this as long as you do periodic check ins to the net.
Also what if one of these cloud services gets hacked and your purchases are wiped out? Probably a good idea to keep a receipt. I'm open minded as long as the prices are fair and we have some protection on our purchases.
Edit: Another article about ultraviolethttp://www.usatoday.com/tech/news/st...ies/52495788/1