Pessimistic economists point to persistent ugly problems with mortgage foreclosures (there are some 2 million homes in foreclosure, about 3 times the "normal" number), mortgage availability (because of tougher standards about 40% of borrowers have FICA scores above 780, about 4 times as many as in 2001) and housing starts, which still haven't hit a run rate of 1 million units.
Fence sitters point to improvements but still "bad" levels of household debt (the debt to income ratio is above 100), a higher but still sluggish rate of household formations (the 1 million new households formed last year doubled the trough rate in 2008 but is still well short of the 1.3 million long-term average) and a stable, but depressed home ownership rate of 65% (the peak was 69%).
Optimists focus on the good news about housing prices (they're rising again and are back to trend), housing affordability (it's once again just a little more expensive to own than rent) and the months' supply of new and existing homes for sale (at just 4 months of inventory, supply will almost certainly fall short of demand during the spring selling season).
It seems to me that six years after the onset of the housing crisis, with housing starts still near depression levels and with the economy steadily improving, the argument goes to the optimists. Housing seems to have nowhere to go but up.