dharmagirl, I’m glad you asked this. I was wondering the same thing a few weeks ago. I found a thread from last year (http://piggington.com/taxes_re_assessed_or_not_after_buying_below_assessed_value) where it was stated pretty matter-of-factly that it would be re-assessed at the new sale price. So I thought I had my answer. But the answers on this thread seem to indicate that the assessor may not necessarily use the new sale price as the new assessed value. I guess that’s why the answers on blogs always require further research.
Maybe a “Steak of the Month” subscription for the assessor will push them in the right direction.