As many will note, I despise Gamestop with a passion, so anytime that I can get 'one up' on them(or seemingly get one over on them anyway), then I'll do it.
Otherwise I steer clear of the place, since the condition of their used stuff is STILL ass to some extent and the amount of badgering that the employees have to do to you from the moment you walk in the door is just plain annoying.
I used to do the trade deals all the time when EB was still around, since I was already getting game deals like the ones I've managed to swing since joining CAG(games for $3-5 each), so trading 3-4 games for one new one was no big deal.
However, since Gamestop took them over, the deals have been few and far between where they would be in OUR favor.
The last really good deal in my opinion was the tiered trade deal last fall for last gen titles(back when GS still took Xbox titles)that just happened to coincide with the $3.99 last gen game sale/clearance at Hollywood Video.
Since then, they've only done deals which are skewed heavily in their favor, but I can't say I blame them since they probably got flooded with shittons of HWV disc only stuff last fall.
I was considering grabbing a couple more sets of games from BBV and trading them into GS for more copies of FNR4, but I have little use for GS credit at this point. That is, unless they're already taking pre-orders on my next game I really want(God Of War 3), which they probably are already knowing them.
Otherwise, I'll just stick to getting my cheap game fix by buying some from Sears, Kmart, Target and TRU.