I don't understand what you mean by this. I'm curious how Half-Life 2, Episode 1 & 2, TF2, Portal, Left 4 Dead 1 & 2, and Portal 2 somehow don't qualify as "serious" games.
My bad, I meant 2004 (meaning Half-Life 2 was the last serious game).
As for the rest: http://agdom.wordpress.com/2010/02/20/a-definitive-look-at-valve/
Good read. You have some valid criticisms, but I disagree with many of your assessments. Left 4 Dead is some of the best multiplayer gaming I've ever had, and I've spent hundreds of hours in both games. Half-Life 2's episodes were both brilliant in my opinion also (you seem to complete games faster than the rest of the gaming curve, by the way, which may affect your opinion a bit), and well worth the money.
Sounds like a lot of the issues you have with Valve are more based around the business model and price points rather than the games themselves. Anyway, don't want to derail the purpose of this thread. Maybe a PM or separate thread if you'd like to continue?