Looking at OnLive's pricing plan, is a bit annoying. The first few games, available, are sold at full price, but act as an extended rental. You pay $60 for Tom Clancy, to play it until July 2013. To keep playing the game, you have to keep paying the monthly access fee. Once you stop paying the fee, you lose the "rental", negating the value of the $60.
Other games, you can rent for $5-$9, and play 3-5 days, before the rental lapses, but you can rent again and pick up where you left off. In this case, you would end up paying, $42 to play Batman: Arkham Asylum for 30 days, and that is not including the access fee.
The prices for the games are at different levels, and there is no standard that is easily perceived (at least not by me).
All together, this makes OnLive cost TOO much, for not enough of a service. There are too many restrictions on how you can connect to play the games (no Wi-Fi, no Linux). Though the idea for the service is incredible, and footage of comparison between running a game locally and on OnLive has been posted on youtube, with good results, I just don't see the current pricing model as usable for those who are really trying to save money on gaming by not purchasing a good PC.
In the end, the pricing is so harsh, that it is cheaper to invest in the $1000 PC, and just keep your eye on STEAM sales.