Which tells you something that is true for all of us who talk about region-wide metrics in any subject... what is going on in your specific neighborhood may be very different from what is measured for the region in aggregate. But overall the City proper is doing well compared to a lot of local municipalities and I am at a loss to figure how already near zero housing price in the Mon Valley are continuing to plummet.
Willow also has data for specific city of Pittsburgh neighborhoods. It shows Bloomfield one of the best performers over the most recent year at +10% year over year in value.... most of which came in just the last quarter. Eyeballing the map and matching it to that data seems a little odd to me. Looks like appreciation through a greater Bloomfield/Friendship/Lawrenceville nexus. Can you say Children's Hospital?
Another study out of note on housing is a recent NBER paper (subscription required): Housing Supply and Housing Bubbles by Edward L. Glaeser, Joseph Gyourko, Albert Saiz. NBER Working Paper No. 14193. July 2008.
That report looked at regional housing markets across the country. Pittsburgh housing is relatively cheap by another metric. According to the report Pittsburgh housing can be bought at over a 30% discount to what it would cost to build locally, one of the cheapest values for that calculation in the nation other than Detroit and DallasFort Wayne.