Okay, it's not like the good old days of 2002–2007, but there are some grounds for concern in certain markets. In particular, the Case-Shiller tiered price indexes are showing extraordinary increases in the bottom tier (lowest third of house sale prices) in several markets.
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These numbers should provide serious grounds for caution. This is not a story of a bubble whose collapse will sink the economy and cause a financial crisis, but there is a real possibility that a lot of moderate-income homebuyers may get badly burned if prices turn around. The real estate pushers never care, since they make their money on the turnover, but it won't be a pretty picture for the families affected.