Plus there's a lot of rental properties now that would have been sold if not for taking a huge hit in market value from the housing bubble collapse. I wanted to sell my townhouse 2 years ago but I lost $25k in market value from my purchase price and I already sunk $15k in improvements. No way I can recoup that right now so I rent instead and wait for the value to come back up a little while paying down the mortgage to a point I can get equity out when I do sell. It's a waiting game.
There's a ton of the above going on right now, but IMO it's been bad for long-term housing prices vis-a-vis supply and demand. Tons of people who want to sell, have not.
Then you have the wealthier people who are of the belief that it's a great time to buy a house due to the price collapse and the low interest rates, who are buying multiple houses and renting them out on the belief that house prices will move higher from here.
Then you have the opposite side of that coin where people think housing could still go lower, and they're waiting to see, and this is creating increased demand for rental properties, which have never been hotter.
Then you have to consider that there are still a ton of "Shadow Foreclosures" that should have hit the market, but the government is preventing them from hitting, which is monkeying with the real estate market both currently and going forward.
Then you have to consider the broader monetary FED policy of QE3 (pejoratively called QE-Forever) and how that will hurt the US dollar and keep the interest rates low for a while and how that effects housing.
Then you have to consider (as you always do) key economic fundamentals like unemployment rate, population demographics, inflation, interest rates, etc....
There has never been a time in our history where there are so many variables up in the air regarding housing prices and where they could go. It's all very complex,and it fascinates me.