I read an academic paper a while back that said land prices have 3 times the variability of housing prices. If you believe that, than land is falling faster than housing.
Anecdotally, on the national level the builders are madly trying unload their land, and are walking away from their options.
Locally, just take a look at the prices for 1 acre+ lots outside of Redmond.
This listing is worth a thousand words:
http://www.redfin.com/WA/Redmond/21201- ... s-280214723 acres, a beautiful house, an $85,000 haircut from 2006, and still sitting.