1) it's unlimited at $8 unless you still have access to the $5 plan which did have limited a streaming.
2) Amazon's storefront for streaming sucks, their recommendation engine sucks, they have no queue system, etc. This needs a MAJOR interface overhaul to be worth it.
3) Amazon uses lower bit per second aka lower quality (enough to be easily noticeable per other review sites).
4) Selection selection selection
5) I happily pay $2 extra to be able to get those DVDs in the mail, for a large number of reasons.
6) no consoles, no phones, etc. Netflix is entrenched here, Amazon is barely plugging along with some simply support forthcoming for some TVs and set tops.
For people already paying for prime, this was a nice bonus. Personally, i could care less about the 2 day free shipping for $80 a year vs just waiting 2 more days for free...
nice to see competition enter the game, but its going to be a few years before Amazon can compete, and netflix has the market and the capitol to put of a hell of a fight.