There has been much talk of the new MacBooks whilst being most desirable, are also a bit toasty when running. Well it it seems that some models may be running too warm due to a piece of protective plastic film being left covering the rear vent. After several people discovered this for themselves, Apple released a document on the subject:
“Some MacBook computers may appear to be running too warm, with the fan running consistently and heat emanating from the top and/or the bottom of the computer.
If this happens with your MacBook, check the rear vent of the MacBook to make sure it's not blocked.
Some MacBooks may have left the factory with a thin piece of clear plastic covering the rear vent. This is used in the factory to prevent dust from getting into your computer. If your MacBook has the plastic still over the vent, simply remove and discard it.�