I own the Nikon AF 80-200mm f/2.8.
It is a great lens, and half the price (new) than the AF-S 70-200 f/2.8. If you don't need AF-S or VR, it is a great lens for an amateur photographer that may not be able to afford the AF-S 70-200mm f/2.8.
And it is one of the few times that both Thom Hogan and Ken Rockwell agree that it is a killer lens.
Nikon did make an AF-S version of the AF 80-200 f/2.8, but they only made it for a short time - perhaps a year or two, around 2000 or 2001, before coming out with the AF-S 70-200 f/2.8. Consequently, they are hard to find in the used market.
I use my AF 80-200mm f/2.8 with a D90. And before I bought it, I did a lot of research.
If you look at reviews, there is some criticism about slow focusing with the AF 80-200mm f/2.8. However;
this lens has been around a long time, and there are several models made.
The original model, from the late '80s~early '90s, was a "push-pull" zoom (meaning you push the zoom in and out rather than rotating a zoom ring). Those were the first generation of this lens, and they are the ones that were the slow focusing lenses - about 3sec from lock-to-lock.
Lock-to-lock means the complete cycling of the focus mechanism when you depress the shutter half-way with the lens cap on.
In the '90s, Nikon changed the design, and went to the familiar twist ring zooming mechanism and improved the focus time. My lens (it was new in 2011), has about a 1sec lock-to-lock focusing time.
In contrast, the Nikon AF-S 70-200 f/2.8 has a 0.6sec lock-to-lock, and the Sigma 70-200mm f/2.8 has a 1.4sec lock-to-lock focus. So the AF 80-200mm f/2.8's focus time is comparable to it's competition.
One thing that is interesting, the focusing of this lens on the D90 is faster than the normally higher regarded D300s. I am concluding from this is that the D90's lens motor has a higher torque rating.
There is also a focus limiter on the lens that can help speed up the focus as well, and I have found focusing is less than 1sec on my D90 when using it.
As far as sharpness, the AF 80-200 f/2.8 is very sharp. While the AF-S 70-200mm f/2.8 is sharper, it is more or less a measurable difference than a noticeable one. On the scale of 1-100, the 80-200 is about 98 and the 70-200 is 100.
If you are on a budget, you can buy the old model 80-200 (push-pull) for around $500.
A used twist zoom 80-200 is about $950, which means these lenses hold their value, and may even appreciate. But some of the older twist-zooms have a weak manual/auto focus switch. The switch ring tends to crack, and about 80% of the used ones I saw were cracked. This does not prevent proper use of the lens, but it is an annoying thing for a > $1,000 lens. But those rings have been made for 15 years, so perhaps the new lenses will not have those issues.
If you can find an AF-S 80-200mm f/2.8, they run about $1,500.
At any rate, I went with a new AF 80-200mm f/2.8 last year as it was half as costly as the 70-200mm f/2.8, and the lens holds it's value, so I figured I would not be losing anything by buying a new one.
And I have not been disappointed. The only issues I have had is sometimes I can get a focus hunt when tracking high-speed aircraft, but even then, it only happened twice in 100 photos. And that is the worst case scenario as you are focusing on a small dot in a huge sky.
If you are a pro, go with th AF-S 70-200mm f/2.8. But if you are an amateur and want a killer lens on a budget, buy a new AF 80-200mm f/2.8. Of course, being an AF lens, it will only autofocus on your D90, not your D5000.
When you go with this lens, you may have to relearn a few things, such as using spot focus and re-visit DoF concepts.
Here are a few samples taken with my AF 80-200mm f/2.8 on a D90:
Bokeh:
http://www.althephoto.com/lenses/bokeh2.jpg
Lens sharpness:
Original:
http://www.althephoto.com/lenses/tiger-small.jpg
Extremely cropped photo from the original photo above (notice the eye whiskers):
http://www.althephoto.com/lenses/tiger-large.jpg
Nine-blade diaphragm (great star patterns):
http://www.althephoto.com/lenses/af80-200-1a.jpg
Oh, one last comment. This lens does not come with a lens hood. The optional bayonet hood from Nikon is about $35. I bought a 3rd party bayonet hood for about 1/4th of the cost of the Nikon hood.
http://www.amazon.com/Adorama-Dedicated-Lens-Nikon-80-200mm/dp/B001CNERU8/ref=sr_1_2?ie=UTF8&qid=1345056982&sr=8-2&keywords=80-200mm+nikon+lens+hood
I also have the 18-200mm lens (the 80-200mm is very heavy), and I use it for vacations. The webpage below shows the differences in sharpness between several lenses, including the 18-200 and 80-200. I use the 80-200 as my benchmark lens.
http://www.althephoto.com/lenses/superzoom.php
If you compare the photos, you can clearly see that the 80-200 is a superior lens.