I don't realy see the point, in most cases, of revising the older 3rd-party products. The new material, which must be included in the SRD to be considered as usable, is exactly that: NEW. While a few books might revise themselves to add this extra material to thier feat and spell lists, most of it will rpobably fall into the "too much hassle" category. In addition to this, much of the top-selling PDF files focus on material that is not really affected by the inclusion of the splat-book additions (c'mon, what else do you think they would put in?): psionics suppliments, books of extras for magic users, ect.
BTW, anybody know, or can direct me to, a complete list of WHAT is being included? SO far all Ive gotten is vague hints about "material from other WotC books". SO far it seems like they are going to be puting in the "well, duh" stuff from the splat-books, such as Eschew Materials and other must-have-for-flavor feats, but no hard data.