will the price drop significantly after the new one comes out? Because I'm assuming the new one will come out with the original price tag (2000+)
Yes, IF a new one is released (and that's a big IF, since a 24-70 II or IS has been 'coming soon' since 2009), the price tag on the new one will almost certainly be a significant jump from the current version (my guess would be $400-500 more).
The thing is, because the current version will be much cheaper by comparison, there will be no price drop on the current lens (new or used). In the case of the 70-200mm f/2.8L IS II, the prices on the MkI version of that lens actually went UP after the new version was released, because even a higher price on the older version seemed like a bargain compared to the price tag on the new version.
There is even a possibility that prices will jump a little. After the 70-200mm f/2.8l came out, prices of the old lens jumped. It was much less expensive than the new one, so up went used and new prices.
Prices were sinking slowly until the earthquake hit Japan, and will probably start dropping again.
I've bought several used 24-70's in the $600-$800 range, and one new one for under $1000 over the years, but prices have jumped. I resold all the used ones, and returned the new one, they just did not suit me quality wise, even when manually focused very carefully, the images were good, but not quite matching my 24-105mm L.
I'd be interested in a newer version, but pretty cautious, since I have grown to prefer primes for their wide apertures. If new cameras manage a 2 stop jump in low light capability, which I doubt very much, I might actually find f/2.8 usable in very low light at fast shutter speeds.