TurboTax 2011 for Mac and iPad has the Property Tax Entry Field Grayed Out
This occurs when there are supporting details for property tax in your 2010 return and that return is transferred into your 2011 return.
How to Solve
Mac Solution: Simply double-click the Property Tax entry field and you'll be able to add supporting details and the amount of any property taxes paid in 2011.
iPad Solution: Unfortunately TurboTax for iPad doesn't handle supporting details at this time. You will need to transfer your return into TurboTax for Desktop.