This is the standard lens for news, sports and action and environment portrait shooters. It's light weight mechanically and optically precision built and the 70-200mm VR shines for fast action in low light. Its rated as one of Nikon's sharpest lenses ever and its sharp at every aperture. It is famous for its beautiful bokeh (that gorgeous out of focus background look) The 2.8 aperture makes this a 'fast' lens.
I also have:
Macro lens for insects, food and tiny stuff. Also one of the best portrait lenses you can get. Again beautiful bokeh.
Good optics and considering the low price and the long focal range, very good all rounder in performance.
The wide angle lens if you're on a budget and the the sharpest ultra wide lens for a DX Nikon camera. It's rated better than the more expensive Nikkor 12-24mm.
Great for landscapes, architecture and anything inside or close range and low light.
Why 2.8 ?
The maximum aperture of the lens can have a significant impact on the types of photos you can take.
Smaller Aperture number (2.8) = Wider Aperture (the hole) = More Light
Larger Aperture number (22) = Narrower Aperture (smaller hole) = Less Light
If you want to take photos indoors without a flash, on overcast days, for sport or anything you need to use fast shutter speeds to freeze motion you need a fast lens (2.8 or better)
You can also get a shallower Depth of Field (DOF) DOF is that amount of your shot that will be in focus. With a large aperture you get a large depth of field, that is most of your image will be in focus whether it’s close to your camera or far away. With a small aperture you get a small (or shallow) depth of field and only part of the image will be in focus and the rest will be fuzzy (bokeh) but this separates the subject from the background (as long as IT is in sharp focus) and give a 3D effect to images and smoothes out busy backgrounds. - see RedBubble Flickr