The special tax rate on long-term capital gains is set to expire on December 31, 2012. In 2013, if Congress does not take action, the tax on long-term gains from a sale of a business will increase from 15 to 20 percent. Additionally, the distinction between ordinary and qualified dividends will disappear, and all dividends will be subject to the ordinary tax rates.
Also beginning in 2013, capital gain income will be subject to an additional 3.8 percent Medicare tax.
http://www.martinwolf.com/Websites/martinwolf/images/White_Papers/Capital_Gains_Tax.pdf
This means that Romney, and all his millionaire buddies, who only pays 15 pct capital gains tax, will now pay 25 pct, a huge increase in revenue.