One of my favorite guidelines from the Research-Based Web Design & Usability Guidelines is the following:
10:1 Use Meaningful Link Labels
Guideline: Use link labels and concepts that are meaningful, understandable, and easily differentiated by users rather than designers.
Comments: To avoid user confusion, use link labels that clearly differentiate one link from another. Users should be able to look at each link and learn something about the link’s destination. Using terms like ’Click Here’ can be counterproductive.
Clear labeling is especially important as users navigate down through the available links. The more decisions that users are required to make concerning links, the more opportunities they have to make a wrong decision.
My emphasis. In terms of web design and development pet peeves, I hate "click here" even more than I hate opening a new window for off-site links* to "keep people on your site," so it's always nice to have some place with gravity to point to when telling people "click here? that's a bad idea."
*imagine how much I hate clicking here to to open a new window….