These are marketing terms. They mean nothing to me. Do you have any affiliation with any company related to Civilization 5, in any way?
They aren't marketing terms. I wouldn't use them if they didn't refer to concrete things.
By value, I mean the worth I perceive in the game. Steamworks (meaning achievements, the chat client and so forth) adds value for me.
By feature rich, I mean that it's DRM plus the rest of Steamworks. If they didn't give me the benefits, I wouldn't pay the price.
Your cynicism is noted, but I'm not associated with Valve or 2k Games or anything like that. If I have an "association" with any group, it's this: http://forums.somethingawful.com/forumdisplay.php?forumid=44
I'm a massive video game fan and moderate a forum.