However, I never preferred r600g just because it's newer. My post was maybe a bit inadequately worded in the sense that r600g is only about 3 months old but it is basically already on feature parity with classic, does not crash often (haven't in the last week or so) for me(tm).
So assuming that the speed of development won't slow down significantly it very well might bring obvious advantages (speed/opengl, etc) by next April.
Plus some guys are working on a video decoding state tracker for gallium/r600g.
Point is, that I thought they completely ruled out the possibility to default to r600g. However, as bridgman pointed out this is not the case, so *I take my word back*.