Love or hate it, “nom nom” has become more than just a cutesy/annoying Internet thing. It's now a word in the Oxford English Dictionary, recently added along with other food terms like sammich, California roll, and our favorite here in OC, banh mi.
The official entry:
informal, chiefly North American
(also om nom nom)
used to express pleasure at eating, or at the prospect of eating, delicious food: chili and cornbread for dinner, nom nom!
delicious food: there were all kinds of nom noms — onion rings , hot dogs, burgers, and fries
early 21st century: probably imitative but apparently also popularized
by the noises made by the Cookie Monster character in the children's
television programme Sesame Street. Compare with YUM YUM
Sigh. Instead of weeping for the English language, I guess all we can really do is LOL (also a word in the dictionary).