That did not take long. Christopher Brown-Humes in the FT reports on a Merrill Lynch (MER) survey of fund managers that shows a decided turn in sentiment toward the U.S. equity market. In two short months portfolio managers went from neutral to highly positive on the U.S. and have become decidedly neutral on the prospects of former favorite, Japan.

“Two months ago the consensus trade was to overweight Japanese equities at the expense of US equities. The past two months have seen a radical rethink,â€? said David Bowers, chief global investment strategist at Merrill Lynch.

Just Lahart in the Wall Street Journal notes that many on Wall Street want to don the “contrarian” label. Measuring consensus opinion is one thing. Interpreting it is quite another . Simply taking a knee-jerk position against consensus opinion will in all likelihood not payoff, because:

But just because running against the crowd is the cool thing to do doesn’t mean that it’s always profitable, thinks Maxim Group strategist Barry Ritholtz: Only when the crowd devolves into an ugly mob does contrarian investing really work.

However as in the Merrill Lynch survey, there is growing evidence that the market rise has garnered a sizeable following:

So which way is the crowd really leaning these days? According to survey results Merrill Lynch released yesterday, more U.S. fund managers think stocks are undervalued than overvalued. A survey from investment-research firm ISI Group showed that hedge-fund investors’ net exposure to stocks is at the highest level in nine months. A compilation of sentiment measures put together by Ned Davis Research shows that investors are feeling more bullish now than they have for most of this year.

In short, the crowd will be right until it is eventually proven wrong. The question is how long will that take, and what might you miss in the meantime?