I almost wanted to skip this, just like the neighbouring 'tweet' article, but, what the hey! I was just surprised at the cost - $4000, which they described as 'cheap'.
People have been working on cheap accelerometers for houses, for years. There's that one project that uses laptop accelerometers. Are any of these things better than tweets? I think not.
For a seismometer to be of any use, it has to be calibrated. Throwing it into a garage usual means terrible foundation conditions. Can they record minor seismicity long enough to see how the site responds? Maybe, with the big-bucks thing, but at that price I still think it's better to install something nicer.