The Nikon 12-24mm AFS DX is the lens to have if you are shooting landscapes with a Nikon digital body. What we lost when we sent from 35mm to the smaller APS sized sensor is more than made up for but this lens. Sharp from edge to edge and a constant f4 aperture this is a fab lens to get digital shooter back to the real wide angle. It shows very little distortion even at 12mm which means all your lines will appear straight and you can even use a filter with out vignetting.
If you see me out in the field this guy is usually with me. Even when I am shooting birds and mammals with a long lens this will probably be in my pocket ready to grab a habitat or scenic shot.