True, it won't slow the sprawl much, but 10,000 high-end condos in the core means fewer McMansions in Stafford. And unfortunately, I don't think we can build our way into a solution for affordable housing when so many people are making less than $10/hr.
The real check on sprawl will come from increased densities (i.e. mega multi-family housing complexes) along transit corridors in our existing suburbs. That's where most of our future workforce will be living. All the more reason for a more comprehensive high-capacity transit network here, to every corner of the metro area.
Oops, sorry. Back on topic..... yes, we need more towers like this Downtown.