Shiller has certainly been a bear on housing for years, but it is easy to stand on the sidelines and point at something you call a housing bubble and quite another thing to call the peak, especially when you are in the business of selling economic data on housing. Predicting the future is a difficult business in the short term, but much easier in the longer term.
I also think that housing is best viewed as an "income" producing asset, not as a "growth" asset. When you own a house, it throws off the "dividend" of you being able to live there. The value of the investment has to take into account the "dividends" that allowed you to live there all those years. Would you be impressed if Morningstar didn't take into account the dividends thrown off by a mutual fund?