yes, what you are seeing is really happening. I'm an investor, have a loan mod business (residential and commercial), and have my real estate license in 2 states.
There is a "shadow inventory" of homes banks were waiting on dumping on the market so as to not further depress prices. They were waiting for the Toxic Asset Buyout Plan to relieve them of their junk properties and non-performing loans.
That plan didn't work out so well (despite 94% public, 6% private money) since the private investors didn't trust the government from changing the rules on them like they did with the Chrysler bankruptcy where they screwed the secured bondholders and usurped over 100yrs of bankruptcy law.
The lack of confidence in private money (smart money) stalled the plan and now banks are forced with dealing with their own junk themselves not pawn it off on the public.
They will do what they can to slowly dump inventory, but the 3 other shoes to drop are Alt-A, Option ARM's and commercial defaults which will further deprress the prices/ market.
All markets are local, but on a national scale this will further deprress prices. CA has a high inventory of overpriced houses and Deutsche Bank predicts next year over half of homeowners will be upside down (owe more than house is worth) States like CA which had a huge run up in prices will probably have a much higher ratio of owners upside down.
The more upside down the easier it is to walk away, further driving down prices.
Hope that helps