After seeing Tristan Louis' list that tallied the streaming availability of 2011's top 100 box office hits, I was curious what it looked like graphically. So I put together this little number. Blue means available, yellow means not, and gray means it's only available for purchase. The last column for DVD simply means it's available (since DVDs are of course not streaming).
Netflix streaming still isn't a place to find the big movies (as any Netflix customer can tell you), with only five of the top 100 available. There is greater streaming availability from iTunes, Amazon, and Vudu, but those of course aren't fair comparisons to Netflix, given that the latter is subscription-only.
My main takeaway is that if you're deciding between the non-subscription services, it looks like price is the main thing to look at, since there doesn't seem to be much variability in availability (although it could be different for smaller movies). As for Netflix, subscribe for the television and for the movies less so.