I use a Nikon D-200 w/18-200 mm lens, which provides a of latitude. It is a lot to carry around, however, and you don't need to be that elaborate. 10.6 megs are more than enough.
For casual work, an 8.1 mpxl Sony dsc-w150, which has a 35 mm equivalent width of 30mm. It cost me about $200, and is a hell of a camera because it weighs just a few ounces AND has an optical viewfinder AND can automatically crop to 16x9.
The w170 is even wider.
Unless you're Ansel Adams or somebody is paying you, that's all you need.
That, a good eye, patience, and Photoshop.