Starting in 2013 a second surtax boosts the top rate on capital gains and dividends to 18.8% from the current15% nominal maximum rate that we expect will be in effect for 2013, plus an additional 3.8%.
An ugly example of this surtax is if you sell your primary residence, the portion of the profit over the $250,000 or $500,000 exclusion will be subject to the tax if your AGI is high enough to trigger it.
The full profit on sales of rental properties and second homes can be hit by the surtax. Also note that the taxable gain may push your income over the surtax thresholds. So a common strategy for 2012 will be selling highly appreciated assets now instead of 2013.