Unless Congress Acts long term capital gains rates will go up 5% next year. Not huge, but not great either. If you can take gains in 2010, you’re better off than taking them in 2011. You can always rebuy the stock in 30 days. Additionally, this might lock in any gains which might be reduced after the beginning of the year due to the market adjusting for the tax. Short term rates remain unchanged. The other problem if Congress doesn’t act is the alternative minimum tax. If you recognize large capital gains, you might incur AMT in 2010, but clearly could trigger it in 2011 due to lower thresholds in 2011. So, if you’re thinking of selling things off in 2010, have your tax advisor run the AMT numbers for you.