My home scored a 58 out of 100. Interestingly, a year ago my house scored 62 out of 100.
WalkScore.com uses the
Google Local Search API to find local stores, restaurants, schools, etc. I noticed that the local results don't show a few of the nearby restaurants (including the brew pub that's a 12 minute walk from my house). I guess that shows some of the limitations with Google Local Search.
As well, WalkScore doesn't account for Public transit, Street width and block length, Safety, Pedestrian-friendly design, Topography, Freeways and bodies of water, or Weather. Not a perfect tool, but not a bad one either.
Tim