This would be based on whether the omniscient creator is a part of our universe or outside of our universe, I'd think. If that creator is apart from our universe* then the scope of their knowledge would be greater than just all that exited in our universe by some unknowable amount.
Never thought about that, but I'd think so too: If the omniscient creater is in our universe, it's knowledge is limited (well, limited to everything in this universe...still pretty much knowledge I'd say^^).
But either way...If there is one, wouldn't it be pretty boring for it, to just sit (or float or whatever) there looking around? Especially of you're omniscient?
Being omniscient must be the most boring thing possible xD