DieRuhe: Didn't really expect to be posting this, but: update!
So after contacting Steam (re: mistakenly bought Sleeping Dogs 64-bit for my 32-bit system) and getting what seemed to be a pre-generated, generic response that really didn't address anything I brought up, I wrote back and said, basically, "Forget it. I can't use the game, you can't actually read my message and understand my issue, so I give up. It'll just sit there in my library and I'll continue to do nothing with it." I had resigned myself to chalking it up as a loss - especially since I bought it on February 5. Yes, over three months ago.
So today I get a message that I got my refund. And not within the two-week period, but over three months. Of course, I'm sure it helped that I couldn't do anything with it and hadn't even downloaded it. So anyway, to the person who told me to "suck it up" because I made a mistake: glad I didn't listen. :-)
You can actually get refunds up to 6 months. Not sure if this is limited time only to give people a chance to get back some money. But On Monday I put in for 4 refunds dating back to December and they all come through and my account got credited today so I bought Duck Game. Initially I tried to get a refund on Dieselstromers since the Devs are useless and not really supporting their game in a timely manner and blaming peoples PC for the terrible optimisation but that was from last September but steam told me I cannot get a refund on that because it is older than 6 months. After that I went though every steam purchase I made of games I played for less than 2 hours for 62 2 months back and got full refunds, so yes, 6 months is the limit at the moment at least.