MathOverflow works very well for mathematicians, in part because it is run by mathematicians, who understand how mathematicians interact. One clever thing they do to make the site useful for the research community is to redirect some questions to the math.SE site. That seems to work very well. (When they have spare time, they do visit math.SE and answer questions.)
The proposal to create a similar place to redirect basic TCS questions was quickly dismissed on area51, because people there disagree with having two sites on the same topic with different lower bounds. On the other hand, they have nothing against the MathOverflow/math.SE model because they view MathOverflow as being outside SE. (Which, frankly, mixes technical issues --- who runs the site -- with social issues --- who participates in the site.)
It seems to me that both SE people and TCS researchers might be happy with migrating the TCS researcher community outside the SE network and have it run by TCS researchers. What do you think?
PS: Just to be clear, I do not feel that we should move, but I think it's an option that is worth discussing.