I've seen netiquitte in regular use since 1994, which was my first contact with the net. Actually, I think I saw it more frequently back then, when most people didn't know the "rules" of the cyber lifestyle. It was so common back then that I simply assumed that it was simply part of (and as old as) the net. It recently occured to me that the word has declined in usage. I assume the reason is because there are so many people online now that it would be difficult to impose politeness rules on the masses.