Dragonblade
Adventurer
What I can tell you is that the demographic seems to have changed from 3.x to 4e, according to the owner of my FLGS. Around here, 3.x was bought mostly by older males (25+). 4e has a much higher proportion of women and kids buying it than did 3.x, as well as gamers who lapsed and are coming back. I do know the D&D Delve Night for January (part of which I'm running) is booked solid, but during 3.x's reign similar events had virtually no attendance. Make of that what you will.
You make some interesting observations here. My circle of people I game with actually enlarged with 4e due to 2 lapsed players who quit D&D during the 3e era coming back, and one of my friend's wives was going to quit playing altogether. She is a casual gamer who has no concept of the rules, but she really likes the RP stuff. She hated 3e, but is much happier with the 4e powers system and her enthusiasm for playing has dramatically increased.