FX has some major advantages over DX.. larger viewfinder, larger sensor (so hypothetically better image capture), most of the bodies are extremely well built and reliable. The disadvantages are that FX bodies are much more expensive (usually associate with PRO gear) and heavier, and good FX lenses are expensive also. The DX bodies are much more affordable, and will use both DX and FX lenses. Still need to buy good glass, even with the smaller sensor.
There are some situations where the FX will shine.. if you shoot pro, and need the absolute best possible image to sell. 90% of the time though, you would hardly be able to tell the difference if you shot the same shot with a good DX. That 10% is what makes the difference though.
Really up to you, what you can afford, whether you intend to shoot in an area where that 10% might make a difference, etc.... and whether you can live with the smaller, non-pro ?? version...
If I needed it, yes.. I would shoot FX... but I don't! I love my D7000 DX... and as of yet, have been very happy with it.