Thats right, as of the next patch, Blizzard will permanently (or so they say at this point) remove the ability to eat or drink once flagged as being in combat. This is to resolve game balance issues that are occurring so far in the Beta. This info is as per the thread going on over on the www.worldofwarcraft.com forums.
The info from the Blizzard side is from EnoYls, and he has a few posts discussing the changes in the thread which can be found here .
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