Like they have said ^
However, these cards are not strictly speaking next gen either, there still building on existing tech. Although, more of a jump than the 88-98 series we hope

.
Apparantly nvidia have yet another dual chip card on the way, running a 55nm version of the current 9800GX2. So, expect a smaller, faster and more efficient 9800GX2 (9900GX2 possibly), but not night and day quicker. Same goes for a supposed 9900GTX, a shrunk down 9800GTX, with quicker clocks. I dont think we will see a proper new part from nvidia till end of the year.
As far as ATI go, R700 may not be as brilliant as its being hyped to be, but then, all of this is just rumour, it should still be a very capable part. But again, its building on R670, which in turn, built on R600 so thats still not a truly new part.
Then again, all this building upon and improving is what has went on for years, the drivers have as big a say in this stuff as the parts them self. The market it seems wont be satisfied, untill crysis is absolutley desimated by a card that is affordable to the masses (as in sub £200).
As for when, as the OP stated, 'proper next gen' parts are out. Not any time soon.
Martyn