I saw an article referenced on the Wall Street Journal's webpage and found the analysis to be interesting (but that may be because I am a dork). Basically, they use the frequency each columnist uses specific, unique words and then apply that to individual columns to see if they can determine the author of the different columns.
I think the most interesting part was the list of the top words and adjectives/adverbs used by each author.
Robert B Parker, who wrote both the Spenser books (there's about 40, I believe) and the Jesse Stone books, and at least one other series, died today. I loved the spenser books. Like reading candy. Read one anytime, fun and forgettable.