While the following is purely rumour at the moment, it seems highly likely that Nikon will be introducing another digital SLR in the near future as a competitor for Canon's D30. As such it is likely to be more of a "D100" (i.e. capabilities along the lines of the F100) than a "D2", although it's widely speculated that it will use a 6 MPixel sensor.
Unless you absolutely need the facilities of the D1 such as it's high continuous shooting rate you might like to wait a bit and see what happens since you could have the third alternative of the new camera and one of the AF-S lenses.
As to the AF-S lenses, you might like to consider going for the 28-70mm first since this would represent a significant quality improvement over your 24-120mm. The case for the 80-200mm is not so clear cut unless you want the very fast autofocus, since I understand the older push/pull version (Nikkor AF 80-200mm f/2.8 ED) is it's equal in optical terms.
Going the other way, the D1 is capable of excellent results at 10" x 13", and can go beyond this. I've successfully made "Super A3" prints (printed area about 12" x 18") with my Epson 2000P: these look slightly soft when you're up close, but at a normal viewing distance they're fine.
Your worries about the D1 becoming obsolete are understandable, but look at it this way: if the camera gives you the facilities and resolution you need then does this matter? You'd have to be very sure, though...