From the link (and it's consistent with the original source from NBA.com, since the salary cap was the same for 2010-11 as 2011-2012 - in other words, a 20% increase from 2010 is still a 20% increase from last year).
Two weeks ago David Stern mentioned that he expects NBA revenue to increase to $5b for the year that ends on 6/30/13.
This would be approximately a 20% increase in revenue over the year that ended on 6/30/12.
If this turns out to be true, there are significant ramifications that this would have for the league, their franchises and the Salary Cap/Luxury Tax thresholds.
The Salary Cap would increase from $58.04m to $69.65m and the Luxury Tax threshold would increase from $70.3m to $84.4m.
Uh, this has so many potentially interesting/important consequences. I would guess that Stern has good reason for making his estimation, because I doubt he'd risk seriously misleading the league's owners...etc..