Yeah there were some requirements:
Need to have the jewel case with barcode.
The original article I read indicated that they would give you the next gen version, but it turned out to be the current gen version. It's still a good deal when I upgrade AC4 for $10 to the PS4 version digitally.
And yes, it was any game. I mean you could have traded in those Burger King games from way back when and they would have taken it. I personally traded in NHL 12, my friend traded in UFC 2009. I was thinking of trading in the Bourne Conspiracy but...
Someone traded in the Xbox Live arcade disc from way back when, so you really could trade anything in.
Also, the store I visited said they had enough copies for 560 customers, but I'm hearing reports that they have enough to restock and continue for the rest of the long weekend here.
That being said, I bet if I went on Craigslist right now, I'd find so many of these games for sale haha. Hate the hoarders that ruin it for everyone, and the line cutters that do the same.