I'm not really that hyped for this giveaway system. At least in the Summer sale despite most of the stuff being pretty worthless, I liked it because there were a few items I definitely wanted to get and just worked towards them. And a few things were awesome like Defense Grid DLC.
But with this, it's so random, and you're likely to get crap no one wants. Like I just got a 50% off Killing Floor. The game is 50% off right now. It will probably go cheaper on a daily. If someone wanted Killing Floor, why would they wait until after the sale to get it?
I read above someone got the Valve Complete Pack. That's pretty awesome, but since it's random, it's not much of an incentive (for me at least.)
I'm probably still going to participate (just for games I own or already wanted to buy) because it gives me motivation to try games I've never touched like Anomaly: Warzone Earth today. But I hope either the system gets better or they never repeat it.
Edit: Thinking about it, if I get one random game I'm mildly interested in I guess I'll be pretty happy. I just got cosmetic stuff from the last sale except for the DG DLC and was happy with that.