I feel pretty darned confident that we will not see material from any WotC splatbooks (be it Sword & Fist or The Psionics Handbook or whatever) in any of the new books. Why? First is page count. With it getting only about two dozen new pages, the PHB, for example, could never hope to squeeze in something like psionics or anything else that big. Second reason (and more important) is that that would undercut the need to buy those other splatbooks. WotC isn't the sort of company that is out to just screw us out of our money, but they are a business, and need to pull in profits. If someone like me (who knows nothing about business) can understand that putting splatbook material in the revised core books means that people are less likely to buy the splatbooks, and thus give WotC less money, its pretty obvious that they won't do that. We may see one or two new things (such as a couple of new feats, and new weapons and spells), but don't think for an instant that this will render S&F or MotW obselete. That's counter-productive for WotC, and they aren't that stupid.