I planned to buy two games per week and ended up with:

Arx Fatalis
Divine Devinity
Fahrenheit
Jagged Allience 2
Outcast
Sanitarium
The Whispered World

In between I also bought Tales of Monkey Island. So altogether I bought more than I planned to do.

Well judging from the Top Sellers list (if that is even a good indication) it seems they didn't do too bad, given that all the top sellers are games that were in the promos, and I noticed while browsing that some of the games in the promos jumped quite a bit in the bestseller list. But again, I don't know how reliable those lists are.

I haven't seen such a thread yet, but I do know what you mean. Sometimes it almost feels like they're justifying a higher price on the extras alone, and occasionally I find said extras to be seriously underwhelming. A couple of wallpapers or avatars icons that could be readily findable online don't quite feel the same as behind the scenes footage or a soundtrack, or even a manual.

...gods, when did Manuals become extras?

Only icredible machine mega pack, since most of the games I was not that interested in and my budged was too limited^^

I bought zero games and was gifted Red Baron Pack.

I thought about buying some like Incredible Machine, Scratches, and Syberia but ended up passing.