In the defense of CoreLogic and also the Case-Shiller home price index which I follow, I have not noticed a pattern of positive spin on the data, and certainly nothing like what you see out of the NAR or the NAHB in their releases regarding housing data. 

I tend to agree with you however on your view of the relative lack of importance of the one-month trend of stabilization of non-distressed sales.  I would claim as an amateur economist that what the February CoreLogic figures showed is likely not a sign of stabilization in the housing market, and in fact we need to see just the opposite, i.e. we need to see the gap between non-distressed prices and distressed prices shrinking, if we are looking for stabilization and signs of strength in housing.

Right now, we have that huge price gap-- foreclosure properties are discounted more than 35% at last check-- because the ordinary buyer who wants to obtain a home for themselves to live in is shut out of the foreclosure market to a large extent because they cannot get financing-- worries about obtaining clear title being a large part of the problem.  Since many of these sorts of buyers currently have little to no choice but to buy a non-distressed home or not buy at all, demand for non-distressed properties is artificially increased, and demand for distressed properties is decreased.  When the gap widens, like Corelogic reported this week, that is merely a sign of more turmoil and greater distortion in the foreclosure market-- a bad thing if you are looking for a sustainable recovery in housing prices anytime soon.

That gap simply has to shrink eventually-- the question is, how soon.  Eventually, I think the foreclosure problems will be alleviated somewhat, perhaps by the 50-state settlement over servicing abuses that is being kicked around.  Once it becomes a little safer and a little easier for the average Joe and Jane to buy a foreclosure to live in, they will start doing so.  That will both bolster demand for foreclosures and take away from demand for non-distressed properties. 

That's what's got to happen for real, lasting stability to return to housing prices-- we need ordinary people to start buying foreclosures to live in.  Anything else is not a true and sustainable sign of pricing strength.