Found a post on Techcrunch about Zillow starting to add user generated data to its Zestimate on Wednesday morning (I assume that is Seattle time, so another 6-8 hours). Actually they are providing two zestimates; one based on public records and one on user generated data.
As put by Michael at Techcrunch "I would expect people to be aggressive about updating Zillow information when they put their home up for sale".
So situations like the one "about a seller who immediately pulled his home off the market after a prospective buyer confronted him with a Zestimate $500,000 below his assessed value. His conclusion is that Zillow.com has made his home unmarketable." Read more here at BloodHoundBlog.
Update at 9 a.m. CET
Just after completing the post above Drew (active blogger at DrewMeyersInsights and Zillow employee) found me being online over Skype and we started chatting. Drew told me that the new release (called z2) has been launched (a few hours before deadline). Zillow's Chairman and CEO Rich Barton has posted an entry on their blog about their thoughts.
Here you found how the update process is executed. You first has to prove that you are the legal owner. There are three ways of doing it, including faxing(!) legal documents to Zillow. Could be quite an effort for Zillow to handle internally if millions of homeowners prefer this method. Finally, I guess all brokers will put some "pressure" on the seller to update their home at Zillow before putting the house on the market.
Update at 8.30 p.m. CET
US has waken and so has the Real Estate blogosphere. One know what was going to happen... Zillow does something and quite a few people have very strong feelings about it.
My call? Believer to 100%.
If I were moving to US, I would indeed be using Zillow. Should I take the Zestimates for granted? No, but it is for sure a better starting point then nothing moving to a new place. Especially by comparing different suburbs to each other (the heat-maps are brilliant).
It seams that some people take credit of the new functionality added on Zillow (see the comments on the techcrunch post). Please, don't underestimate the people at Zillow. I don't know about their product roadmap but I'm absolute convinced that this has been on their horizon from the start. I also believe Ardell at Seattle Rain City Guide is on to the next step in her comment to this post...