Crysis 2 is my single most wanted PC game currently available. The amazing thing is, that $21 is still too much for my blood. I've grown accustomed to paying about $12 or less for EVERYTHING. It's so hard for me to even think about paying more than say... 18 bucks. I think if Crysis 2 was $18, I'd snag it. As huge as my backlog is, I'd have to fork over the $18.
I've got a ridiculous backlog at the moment, so no use in adding more games. The only reason to add a new game to my backlog is if the deal is just too good to pass up. For example, Assassin's Creed 2 recently sold for 4 bucks. When I found out about it, the deal was dead, but I would have bought it without hesitation, even though I have no intention of playing it right away. A deal like that is just a no-brainer, and you gotta grab it when it's there.
Many games for $5 are absolute no-brainers as well.
I'm not sure what I'm going to do when Skyrim comes out, because I'll be so freaking tempted to pay full pop for that baby, but I really should wait for a few patches to come along before even thinking about such an ambitious game.