If you're not experiencing any issues, I would not recommend updating either. Not updating won't cause physical harm to your television set, but updating probably won't hurt the unit.
I wouldn't necessarily recommend NOT doing it, either. There are often some improvements; however, if your set is calibrated, all of those calibrations will go away, as the unit will default to the factory settings on the firmware update. So you may have to retune your television. But it won't hurt it. It will install either way, but not necessarily address a problem that you're having.
Also, only update from the Samsung site that pertains to your country, for instance, U.S. sets from Samsung.com, and Canadian sets from Samsung.ca
I hope that helps, and I apologize for the delayed response. I missed your post somehow, and I regret the oversight.
I just purchased a LN52A750 that came with firmware 1010.2 loaded. I know Samsung recommends against updating the firmware unless you are having issues. I am not having any (awesome TV!) so I'm not inclined to update.
However, the 1012.2 description of 'prevention: The TV will turn off and on continuously' has me thinking I should. I've seen a post of someone having this issue with fw 1010.2 and they had to get the motherboard replaced. So my question is, is this error caused by the firmware errors alone or does it stop the power cycling when this underlying hardware issue occurs? I'm wondering if with 1012.2 you would still need a service call for the hardware issue but the TV would at least not power cycle. Please advise on if I should update. Thanks.