A popular variant spelling of lurk more. It is an expression used when someone demonstrates their ignorance of the customs and social expectations of an online community, or otherwise makes an idiot of themselves online. Its use indicates that the person so instructed should gain familiarity with the community before posting further.
annoying_n00b: LOL @ my genius! I am the greatest! Surely everyone loves me by now.
everyone else: LURK MOAR