Upgrading Advice!

I'd say wait for the D90 replacement to come out and then see if you can get it at a better price at that point.  Don't settle for the lower end models in this case unless you want something lower end than the D70s (for what actually matters).  The D90 should be a nice-and-worthwhile upgrade over the D70s and is designed for advancing amateurs/prosumers -- not too much camera at all, if you intend to get more into the hobby.

Actually, if you really want to get into macro photography in a more serious way, you might even consider hunting down a D200 for less than the D90 price.  I forget whether the D90 can handle manual AIS lenses, but for serious macros, you're gonna need to focus manually and use a tripod much/most of the time, so you might do better w/ limited cash to hunt down some used, manual AIS macro lenses for that (and also get the D200 for less).  Instead of the 60mm f/2.8 micro, you can then go for something like the old, manual AIS 55mm f/2.8 micro for less than 1/2 the price -- I think I paid <$150 for mine off eBay, IIRC.  A used, manual AIS 105mm f/2.8 micro would also be waaaay cheaper than the current VR version -- although having VR on that lens would be nice for all-around use -- and you're probably gonna end up wanting something longer than 55-60mm at some point (if not real soon).  The 90-105mm range seems most popular for general macro photography, and you could also check out older Tamron and Sigma macro lenses for this to keep it affordable.

Alternatively, if you don't intend to be *that* serious about macros, you might consider picking up a Nikon 6T closeup filter "lens" instead and use it on various quality lenses instead -- it's a popular option even for Canon shooters.   On an APS crop body, you can use the 6T on lenses like the 70-300mm VR or one of the 70/80-200mm f/2.8 on the market -- though you'll need to add a step-up or step-down ring depending on the lens.  You can also use it on one of the Nikon tele primes, if you get one, eg. 85mm f/1.8 is affordable and versatile enough (on a cropped body) to own w/out feeling like overkill.  You can use it on lesser teles, but generally, you'll want to use it on the sharpest, highest contrast teles you can afford in order to get good enough quality results -- well, "good enough" is of course subjective.

Hope that helps...

_Man_