I also considered the Nikon 80-200mm F2.8 for my D90, and compared it to the second version of the Sigma 70-200mm F2.8. See Sigma 70-200mm vs Nikon 80-200mm Auto Focus Speed

I ended up buying the Sigma because it was cheaper, and had the HSM AF motor built-in (the Nikon requires an AF motor in the camera body, so the AF won't work with some older and/or lower end Nikon DSLRs that don't have a built-in AF motor), but the AF will work fine with the D7000, which does have a built-in AF motor).

The Sigma also has a 10 year warranty in Canada. Plus also, the only time I tried to evaluate the Nikon (at the Henry's Photo / Imaging Show in Toronto) the demo they gave me to try would not auto-focus at all (I took it as a sign!).

Having said that, my Sigma is currently in being tuned (it was front focusing) and evaluated (sometimes the AF system just stops working - see Reasons for Auto-Focus Freezing). I feel like the Sigma isn't always as sharp as I would like (hopefully fixing the front focusing will help).

If I had to do it again, I might buy the Nikon instead, but I do like my Sigma, and have gotten lots of great shots with it.

I don't think you'll have any problems with the Nikon on the D7000.

I also considered the Nikon 80-200mm F2.8 for my D90, and compared it to the second version of the Sigma 70-200mm F2.8. See Sigma 70-200mm vs Nikon 80-200mm Auto Focus Speed

I ended up buying the Sigma because it was cheaper, and had the HSM AF motor built-in (the Nikon requires an AF motor in the camera body, so the AF won't work with some older and/or lower end Nikon DSLRs that don't have a built-in AF motor), but the AF will work fine with the D7000, which does have a built-in AF motor).

The Sigma also has a 10 year warranty in Canada. Plus also, the only time I tried to evaluate the Nikon (at the Henry's Photo / Imaging Show in Toronto) the demo they gave me to try would not auto-focus at all (I took it as a sign!).

Having said that, my Sigma is currently in being tuned (it was front focusing) and evaluated (sometimes the AF system just stops working - see Reasons for Auto-Focus Freezing). I feel like the Sigma isn't always as sharp as I would like (hopefully fixing the front focusing will help).

If I had to do it again, I might buy the Nikon instead, but I do like my Sigma, and have gotten lots of great shots with it.

I don't think you'll have any problems with the Nikon on the D7000.

I also considered the Nikon 80-200mm F2.8 for my D90, and compared it to the second version of the Sigma 70-200mm F2.8. See Sigma 70-200mm vs Nikon 80-200mm Auto Focus Speed

I ended up buying the Sigma because it was cheaper, and had the HSM AF motor built-in (the Nikon requires an AF motor in the camera body, so it won't work with some older and/or lower end Nikon DSLRs, but will work fine with the D7000). The Sigma also has a 10 year warranty in Canada. Plus also, the only time I tried to evaluate the Nikon (at the Henry's Photo / Imaging Show in Toronto) the demo they gave me to try would not auto-focus at all (I took it as a sign!).

Having said that, my Sigma is currently in being tuned (it was front focusing) and evaluated (sometimes the AF system just stops working - see Reasons for Auto-Focus Freezing). I feel like the Sigma isn't always as sharp as I would like (hopefully fixing the front focusing will help).

If I had to do it again, I might buy the Nikon instead, but I do like my Sigma, and have gotten lots of great shots with it.

I don't think you'll have any problems with the Nikon on the D7000.

I also considered the Nikon 80-200mm F2.8 for my D90, and compared it to the second version of the Sigma 70-200mm F2.8. See Sigma 70-200mm vs Nikon 80-200mm Auto Focus Speed

I ended up buying the Sigma because it was cheaper, and had the HSM AF motor built-in (the Nikon requires an AF motor in the camera body, so the AF won't work with some older and/or lower end Nikon DSLRs that don't have a built-in AF motor), but the AF will work fine with the D7000, which does have a built-in AF motor).

The Sigma also has a 10 year warranty in Canada. Plus also, the only time I tried to evaluate the Nikon (at the Henry's Photo / Imaging Show in Toronto) the demo they gave me to try would not auto-focus at all (I took it as a sign!).

Having said that, my Sigma is currently in being tuned (it was front focusing) and evaluated (sometimes the AF system just stops working - see Reasons for Auto-Focus Freezing). I feel like the Sigma isn't always as sharp as I would like (hopefully fixing the front focusing will help).

If I had to do it again, I might buy the Nikon instead, but I do like my Sigma, and have gotten lots of great shots with it.

I don't think you'll have any problems with the Nikon on the D7000.