I have a MySpace page now.
At LCC, students do on-line class evaluations at the end of each term.
Ideally they would provide thoughtful and constructive comments about the class content and textbook (departmental decisions) and the instructor's teaching style, testing style, willingness to provide extra help, etc. Sadly, students rarely say more than a sentence or two.
Even more sadly, their comments are not accessible to other students wondering about which instructor to take a class from next term. Ideally the comments would be visible anonymously but linked to relevant statistical information (i.e., the brief comment "Easy class" is not very informative if made by someone who always earns A's in math, just as the comment "Very confusing" loses credibility if the commentor has enrolled in the class three times and always drops it during the third week).
There are two websites that try to fill the need of students reading each other's class evaluations. One is at MySpace, and only visible to people with a MySpace account. Some of my students talk about it, and others wanted to know the link. Thus I needed to get an account, to be able to see the page and send out the link to my students.
The other place is RateMyProfessors.com, which I first heard about from P.D.
Needless to say, neither of these sites provides any information about the commentor to help a reader know how much to treat the comment as relevant or credible, and few of the comments are verbose enough to provide clues.
It is also true that often students simply do not know why choices were made or what alternatives are available. For example, a mediocre textbook might unfortunately be the best one available for that topic, or an apparently strange item included in the class's content might be required by state law. But for most issues of this type are not relevant to the reader looking for which instructor to study under: there are no alternatives or reason to select one instructor instead of another.