The official name for this lens is the AF-S Nikkor 10-24mm 1:3.5-4.5 ED DX lens, and in this review I can offer a unique perspective because, unlike most reviewers, I have shot tens of thousands of shots with this lens.
Who is the Nikon 10-24mm lens intended for?
To really understand this lens, you have to understand focal lengths. If you haven't yet seen a comparison of a 10mm lens and an 18mm lens, and how it affects the field of view, then it won't make much sense to you to buy this lens when you already have an 18mm kit lens. Also, you need to know that there is a HUGE difference between 10mm and the 18mm kit lens that came with your camera.
In short, this lens is built for landscape photographers who are willing to pay for durability, and who shoot with non full-frame Nikon DSLRs (such as a Nikon D3200, Nikon D5300, Nikon D90, Nikon D7100, or Nikon D300s).
What's so great about this lens?
Probably the most important feature of this lens is the focal length. Even on a crop sensor camera, a 10mm lens has an extremely wide angle of view. In fact, you have to really watch the edges of the frame or else your feet or the legs of your tripod will be in the picture! This wide angle of view is absolutely essential for landscape photography. It makes the viewer feel like he or she is standing in the place where you took the picture. It draws the viewer in.
After the focal length, the next best feature of this lens is the close focus distance. I heard a great quote a few months ago: “If you want a good landscape lens, just find the widest lens with the closest focusing distance.” Obviously that's too simplistic. There are other factors that impact the quality of a lens, but I agree that how close the lens can focus is vitally important to a good landscape lens. This allows you to put a foreground object up close to the lens and give the photo a sense of depth. I was shocked after first buying this lens when I heard the comforting focus beep when I was focusing on a rock only 9 inches (.24 meters) from the lens! That is simply unheard of in the world of landscape lenses.
The third factor that sets this lens apart from the competition is actually the Nikkor name. I considered buying the Sigma 10-20mm lens or the Tokina 11-16mm lens instead of the Nikon 10-24, but I read so many reviews from photographers that had broken those lenses that I didn't want to invest in a junker. Buying photography gear is a big expense, and I wanted something that would last a LONG time.
What's just average about this lens?
Compared to the optical quality of most other Nikon lenses, I would say that the 10-24 is “fair.” If you're used to shooting professional Nikon lenses, then you'll be disappointed in the sharpness of this lens, but if you are coming from a kit lens or other lenses under $300, then you'll be very happy with it. The sharpness of the lens varies from fair to good depending on focal length and aperture.
Also, the lens does not have a constant aperture. When shooting at 10mm, you can achieve an aperture of f/3.5, but when shooting at 24mm, the lens can only achieve an aperture of f/4.5. This is rarely important, since most landscape photography is done at higher apertures such as f/16 or f/18 in order to achieve maximum depth of field. The only time this is really relevant is when shooting night photography.
What's not so good about this lens?
First of all, the price of the Nikon 10-24mm lens is not fantastic. It costs about $1,000 (check the current price on Amazon here). Right now you can pick up a Tokina 11-16mm lens for half the cost that is significantly sharper.
The distortion on the lens is quite dramatic at 10mm. That's obviously to be expected, but it seems to be more out-of-control on this lens than on other wide-angle lenses. Fortunately, the new lens correction tools in Lightroom and Adobe Camera Raw can help to remove some of the distortion if you want perfect lines.
Here's a link to check out this lens on Amazon.com. You can also buy this lens from B&H Photo or from Adorama if they have a lower price. I would recommend that you only buy this lens from one of those three sources, because I have seen many photographers get scammed from black market sellers online. If the price is too good to be true… don't buy it!