I'm not too sold on Geocommons, a mapping application which is free to use. I am still going to use Google Earth for most things, but I do like how it mashes up data and how it combines KMLs with Shapefiles.
Below is a map of my walks along with a map of the NYCLPC designated landmarks (and some pending ones, too). If you poke around it's obvious how I tailor most of my walks around landmarks.
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