I can only assume it's the same targetted demographic that CivRev pursued and the upcoming CivFacebook hopes to capture; namely, anyone who hasn't already played a Civilization title.
Only in the case of the facebook app does that seem an appropriate target.
Alternatively, there was no target audience. I maintain that the game was terribly managed by the woefully inexperienced Shafer. Someone else, I believe it was Sullla or Luddite (Pi-r8 iirc), who said that the game exhibits symptoms of being designed from a "what's a really cool feature that we could throw in" mentality where features were considered on their own theoretical merits totally outside of any context within the Civilization franchise or even of the gameplay of the actual game.
Yes, 1UPT would fall into that. I've defended it in this thread not because I necessarily support the decision to implement it, but because it has become the scapegoat feature blamed for so much of the game's failings. The irrational hatred for it loses sight of the list of features that were implemented poorly, many of which were more integral to the game than I feel warfare ever was.
My own tin-foil explanation is that Sid used CivRev and CiV as a testing ground for CivFacebook. CivRev had no chance; I don't know that Civilization would ever have translated well to console, and I am positive that the current console playerbase has little interest, if any, in strategy titles. What CivRev offered was a chance to fiddle with the traditional Civilization interface, something that will benefit CivFacebook. CiV suffered the ignoble fate of being a second guinnea pig to test content streamlining on, most especially 1UPT, which I believe will be used in CivFacebook.
That or the corporate culture over at Firaxis has really bought into the belief that designing games for dummies is guaranteed success. They've been shot down twice now, but I actually hope they follow that belief through in making CivFacebook; in this case, I think two wrongs will make a right. Hopefully by CiVI they take heed of the lessons learned between CIII and CIV, or pehaps just of Soren's terrific vision and leadership, if that's really what made CIV so excellent.