Have to ask what you don't like about the D3S, and what would you hope to gain by moving to the D4; and are the differences meaningful enough to you to make the investment? Without knowing what you shoot, your style or technique, there's no way anyone could make a reasonable recommendation. I don't think you'd lose deciding either way, unless you have specific requirements that the D4 would satisfy. Otherwise, you're just getting the "new kid on the block" (and there's nothing wrong with that if, if that floats your boat).
De l'audace, encore de l'audace, toujours de l'audace!