My biggest concern is compatibility with 3rd party products.
If the new books make my whole library obsolete, then I'll just keep using the stuff I have now. I'd have to stop habitually buying every WotC product that gets published, anymore, since it wouldn't work with any of the modules, settings, class books, supplements, and all the WotC books like MoP, that I've bought over the years.
If the new books work flawlessly with my current extensive library, without me having to rework the contents, then I'll likely eventually buy the new books when my old ones fall apart.
FASA used to do reprints all the time, usually without announcing that they'd done so, but the differences were so minor they often didn't matter. I hope that if this rumor is true, WotC's differences are so minor they don't matter, 'cause it would sure suck if WotC couldn' do a reprint better than FASA...