Why Hasn't Someone Sued Zillow, Yet?

So, I was working on Zillow tonight "claiming my listings". Yeah, people don't know all of the little detail stuff we have to do. We have to go into most sites and make sure they are putting our contact information next to our listings. If not "Jane Smith" can pop up next to it and answer any questions the perspective buyer may have. I am not sure how that is fair, but it is. Oh, and did I tell you it was a big pain in the butt?
Anyways, that is not why they need to be sued. As I was "claiming" them, I was noticing the websites "Zestimate". You know the price where Zillow says what it thinks your home is worth. Every single listing was "Zestimated" under what we have them priced at. Now we understand that actual market value is based on what a buyer is willing to pay. However, we pride ourselves on being good at it. Heck we had a 94.57% list to sell percentage in 2011 based on 54 closed listings. To put it in perspective, the entire MLS has a list to sell percentage of like 82%.
All that aside, as a Seller, I would be angry that some website based out of who knows where, is "Zestimating" my home under my listing price. It's hard enough to sell a house in this market, let alone close to what you are asking, without a website putting their two cents in there and telling a perspective buyer that my home is over priced. And believe me Buyers look. To get a home priced correctly there is a lot of science, research, skill, knowledge and a little bit of luck that goes into it.  I know Zillow will say, "oh, its based off of tax records, comparable sales, etc". But to get a true value of a home you need a local professional, that knows the area, neighborhoods, streets and homes. Often times when we go to list a home, we know the comps personally and have been in them, so we can speak intelligently! I don't see how some pimpled faced computer nerd in California can write a program that will ever replace Us.