A map of Real Estate's Web 2.0 universe

We
thought it would be useful to
list and categorize all the Web 2.0 companies and applications in real
estate. Something that would serve as a map or crib sheet for our
clients and
readers.

This is what we have so far.

Please note a few things about how we put this together:

• We only included companies focused exclusively on real estate (e.g., Trulia) or larger companies that actively play in
  the category (e.g., Google). Going beyond that is another project entirely.
• We
  included only companies focused on the U.S. housing market. There are
  plenty of great property sites in Europe, but, again, we wanted to
  present something that lists the most relevant companies, not the
  most.
• It
  is possible, even likely, that we left some companies out. Comment here or give us a
  shout if you have additions. This is going to be a dynamic page.
  Along these same lines, let us know if you think we’ve placed a
  company in the wrong category. There were lots of judgment calls here and these placements make sense to us. But we’re not
  always right.
• Our “blog” category is the most subjective. We only wanted
  to include blogs that covered web 2.0 and online real estate regularly.
  And those
  that are, in our opinion, the best.

Enjoy!