I recently finished this terrific book about the United States Supreme Court: The Nine, by Jeffrey Toobin (2007). It's being widely read at the moment, which is a good thing.
Having studied rocks in school, I don't know much about judicial philosophy. I had a general idea that on one hand there are "strict constructionists" -- people who believe the Constitution should be interpreted according to its words, period -- and that on the other, there are those who believe that the Constitution embodies the venerable principles on which our country was founded and on which it continues, but also note (at the risk of stating the obvious) that everything changes over time, so it makes good sense to apply those principles with that in mind.
I learned that there's a wacky branch of strict constructionists called "originalists," who believe, basically, that we should have only laws that the Founding Fathers would have made, and no others. Never mind all the world experience, social change, and technological advances that have occurred since 1787 -- not to mention the impossibility of communing with the Founders to elucidate their precise opinions on matters before the Court. To oversimplify and editorialize: the originalists, substantially backed by religous wingnuts, are hoping to take over the Supreme Court -- and they might, in fact, do it.
The Nine sheds much light on this and other issues, through a mix of legal history and exposition of the character, values and personal stories of the Justices of the Rehnquist and Roberts courts. Some in my reading group found it too heavy on the case history . We all loved reading about the personalities involved, which are complex and fascinating, and not nearly as easy to like or dislike as you might hope. Tidbits: Did you know that Justices Scalia and Ginsburg have a close friendship born of a shared love of opera, and that their families celebrate New Year's together each year? That Clarence Thomas drives around to NASCAR races (a venue at which you may be unsurprised to learn he is rarely recognized) in his RV during the summer recesses? That Justice O'Connor did her best to get Justice Souter married off during their years on the bench?
The whole thing makes for fascinating reading.
The likelihood of Supreme Court appointments to be made by this administration had my 2008 vote for POTUS decided long before a single candidate had even formed an exploratory committee. If you have any doubt whatsoever about the importance of the current nomination of Sonia Sotomayor to the Court, this book will dispel it. Prepare, too, to do some thinking about what the phrase "activist judge" really means.