Hey I'm new here but I thought I'd give my 2 cents. I just recently put up my site finally after doing web development business for a couple years not having time to put one of my own up and one of the first few tasks I did what put up a testimonials section because if you treat clients well and make sure they get what they want, they will have good things to say about you other than the typical "Well, they do pretty work" reaction you'll get from just looking at recent works. It's kind of cliche like anything else, but as Village Genius said, a good testimonial will provide "who" wrote it and potential customers can investigate themselves if they feel the need. Testimonials are just one more tool of reassurance that future customers will get to know they will be treated well!