On topic I'm still waiting on a definition of 'complete' as applied to RPGs...
Well, clearly it must be a complete game, in that you can pick it up and play without any additional (rules) components, and in that there are no gaping holes in the rules (D&D 4e meets this criterion). It must also allow the PCs to adopt roles - I would argue that it should support a variety of roles, rather than just one, but I suppose that isn't strictly necessary (either way, D&D 4e meets this criterion).
Finally, if the game is expected to emulate a particular setting or genre, then it should include all of the key elements of that setting or genre (a Harry Potter RPG couldn't be complete without some sort of system for Quiddich, for example). Here, arguably, D&D 4e hits a problem, because while D&D has only ever really emulated D&D, there are certain key things that make up D&D, some of which are missing in 4e - specifically enchantment, summoning and illusion magic. (While the naming of the schools was added later, many of the spells existed even as far back as OD&D -
audible glamer,
phantasmal forces,
monster summoning 1 and
suggestion are all present in my copy of OD&D (1978, 2nd edition, reprint).)
Still, as I said in my first post in this thread, in my opinion, 4e is a complete game. It has some significant limitations, which will no doubt be filled in time, but I don't equate
limitations with
incompleteness necessarily.