Well, I've been test driving my Roku for a few days now. So far the things I like best are Crackle and Amazon streaming movies. I signed up for the Netflix free trial, and while it offers some pretty good movies and TV shows, there are very few recent hit movies. I considered the DVDs by mail, but the people I know that have the service say that they can at best get one DVD delivery per week. I think that I'll discontinue the service at the end of the free trial period, and try Hulu Plus. It doesn't have as many movies, but it has most current TV shows.
Things I don't like are the lack of any network TV access (without going through another service like Hulu Plus), and a really good movie service with lots of current films for a subscription price rather than pay as you go.
Overall, though I like the Roku, and would recommend it to others, but I would tell them what they can and can't do with it.