Google announced last month that they will be resuming their series of Panda updates in 2012. If you want to make sure that your website isn't penalized there are three main things you should check.
With the pressure that Panda has been putting on duplicate content, poorly worded and ungrammatical content and excessive keyword use, now is the time to check that your site is compliant with best practice. If you write good, informative content and keep your keyword density to 5% to 8% you should avoid being seen as spamming the system. Don't forget to put your keyword phrase in the first and last paragraphs as well.
Try to use keywords that are directly relevant to your business and location. Long-tail keywords are less competitive and will often rank highly. Using addresses and MLS numbers can also help if you are promoting a listing. Check for
Make sure that you go over all of your links and fix or delete any that are broken. When Google finds broken links they are apt to think that you are running a link farm to spam the system. If you take care of these three major issues your website should be in good shape to avoid any adverse effects of Panda updates.