I looked at one yesterday in a LGS, and they were allowing five free shots. Great trigger, and very accurate. They were selling it for $449 or I might have bought it. Very comfortable recoil. I believe my wife could even shoot it.
I understand that S&W is going to use the Shield trigger on the rest of the M&P line in the near future.
I believe early on the first day of the next gun show in Orlando I will be able to pick one up for around $400.