I have a friend who just built a PC a few months back and is buying up so many things this sale, he LOVES it. I think the first couple sales you experience are always best. After a few sales though, they seem less good than they used to be simply because you already have so much of what you want.
For instance, by day 5 of my first sale I had probably bought over 10 games. By day 5 now, only 2: Metal Gear Rising and now Blacklist. Both new-ish games. So many other good deals, like Witcher 2 for $4 or New Vegas Ultimate for under $7 seem "boring" to me simply because I already own them.
Basically, pretend your Steam library was empty, and THEN tell me the sales blow lol.
Except that daily and flash deals tend to have much lower percentage discounts in recent sales. They also have shifted to feature more AAA titles with ridiculously low discounts, and multiple repeat sales between flash and daily sales. Fewer non-daily/flash deal games seem to be on sale overall, those that are seem to have lower discounts. They have fewer glitches or price errors, the promotional prizes aren't nearly as big, and the general promotion isn't nearly as fun. We went from fun Treasure Hunts to feeble monetized prizes. I would rather have fun playing 30-40 games that are specially discounted for achievements, tracking and competing with friends, all to get a few bits of DLC or the odd free game. That was FAR more interesting and fun than being put on a color team and getting two chances during the sale to try for a random smallish drawing for three free wishlist games, along with hundreds of thousands of others, unless of course I decide to purchase tokens or cards to increase my chances at having proverbial lightning strike me...
Maybe you weren't around back in the day, but Steam sales have noticeably declined since then. If it hadn't been for GMG, Amazon, and GamersGate, my past few Steam sales would have been pretty bad. Now that Amazon has visibly slacked off this year, I'm not sure how the next big holiday sale is going to turn out. Clearly my large library means that I already have bought a large chunk of good titles being offered. I have 450 odd titles in my wishlist though, so clearly I am not wanting for titles I would like to see on sale or discounted more. My wishlist is a wasteland of poor to no discounts.