[Dave]

Compare specification of the Nikon D700 vs D3 vs D300 , plus a review of the main differences between D700 & D3 , in this article here

Previous thread on subject D700 vs D3

[JMitchell]

I think the D300 actually occupies a different market to that of the D700 and the D3, whereas IMO the D3 and D700 are in direct competition with each other.

I've heard so many wildlife 'togs saying they'll stick with the D300 due to the APS-C sensor, they want the crop factor, and I think that is a valid consideration for them, and for sports shooters too.

The D700 on the other hand is a stripped down (barely) version of the D3, and I am not quite sure what Nikon where trying to accomplish with releasing it that early, apart from proving they could put all this amazing technology into such a small space...

[silkstone]

Not everyone wants a portrait grip - either built in or added on - or a camera that's any heavier than it needs to be. If I were a Nikonian I'd choose the D700 in preference to the D3, irrespective of price.

[Kajuah]

The only difference between the d300 and the d700 is the FX sensor in the d700 compared to the DX in the d300 which is essentially what makes it a pro camera compared to the lower classed d300. The d3 on the other hand has a lot more features (such as mpx) but until we can get our hands on a d700 there is no way to see if the d700 has quite the same noise compression ratio as the d3 did at high-ISOs like 25600 or 6400 more likely.

The d3 is 5000 still, at base.

The d300 is 1500-1800 and dropping in america

The d700 is coming out as a d3 + d300 at 3300 $ with the 24-120 mm kit lens.

The d700 has few differences from it's predecessor; and those are extremely few. Like 1 FPS more with the battery pack (MB#) and 4 more focus points than the d300.

The D700 is worth it if you have cash to burn, but you are more likely going to be more successful in investing in a d300 for 1500 $ in the next couple of months and splurging the difference between it and the d700 on lenses.

Though, the full frame sensor on the d700 is tempting it IS a good choice if you are looking for a cheap d3..but the d3 does have the mpx advantage.

As for weight; the d700 is built a bit bulkier than the d300 and is actually only less than 100 grams heavier than it's predecessor.

Like JM said; most people want the crop factor (1.6x?) when choosing the d300.

The d700 is essentially nikon's answer (late) to the canon 5D though, I suspect the canon 5D mark II will leave it behind in the dust. The problem comes in in waiting another half a year for the 5D Mark II. If you're itching for a new full frame camera with pro quality results the d700 is yours.

[JMitchell]

Good comments Kajuah, just to update your question mark, it's 1.5x