I did a comparison of Seattle, WA and Fort Collins, WA (ranked number two of America's best small towns).  Ft Collins is a modern university town and suburb of Denver.    

Both ranked 89!

This shows that exurbs can be as walkable (and bike ride-able (is there a website for bikable?)) as the "old" cities...

This whole walkability thing is all fine and dandy, except it seems to neglect the whole idea that people in sprawling cities frequently work a long way from where they live.  What good is walkability if there is no way to make a living without a car?

That being said, this matrix helps explain how, when I was growing up in L.A., I did plenty of walking and didn't explore the greater part of the city as much as I could have (I grew up in Westwood).  That's not to say I didn't do my part to clog up the 405 and the 10.

What a wonderful idea! I love it, and it needs to continue.

I'm concerned, however, that without some further considerations in their algorithms that the ratings are quite a bit too optimistic and actually unrealistic.  I just put in my address, and it said that it was "very walkable".  Many of the stores that were listed, however, are unreachable or nearly unreachable on foot.  For one of them, I'd have to cross an interstate with large sections of the path having no sidewalk and parts with no space to walk at all (forget about a sidewalk!).  I'd literally be walking in the street with the cars.  To top it off, the streets are busy with motorists that in my neck of the woods try to hit pedestrians and bicyclists.  When I have tried to walk, I've vowed to next time wear hiking boots or just take the bus.

Maybe there should be a "potential walkability" rating along with a "current walkability rating".  It is true that many places of business are geographically close to my addres.  With major pedestrian infastructure improvements, it could become walkable, but I would rate it as "hardly walkable" currently.