I heard hes settimg up his own company, but that he would still assist square-enix but in a diminished role (so it's not all bad)
I got that as well actualy, from a news thread on
http://www.ffonline.com/ and this is what it said exactaly:
Nobuo Uematsu resigns from Square Enix
11.02.04 Mara
The acclaimed composer of music for several Final Fantasy games will begin a freelance career after many years of working with Square Enix.
Nobuo Uematsu will start his own company, although the possibility that he will work with Square Enix in the future remains open.
This is the latest in a series of resignations of high-profile Square Enix employees such as Kazushige Nojima and Masato Katou.