Patrick Maldari, bond fund manager at Artio Global Management, doesn't see that happening quite yet as growth remains anemic, policy uncertainty remains a drag on growth and the Federal Reserve continues to print money. "If you look at the flows, they show that money hasn't left the bond market yet," he said, adding that there will always be investors like pension funds who will hold bonds. (Read More: Fed to Continue Stimulus Amid Signs of Weak Economy)
He still sees reason to invest in bonds -- particularly corporate bonds -- as the returns on the S&P 500 are likely to remain lackluster.
"Over the next few years, if you get a 5.5 percent return on the S&P 500, high-yield debt will outperform despite the current prices," Maldari said, alluding to the strong run up in high-yield debt prices in recent years.
And if the returns on large-cap stocks are likely to remain uninspired, corporate debt can offer similar returns with less volatility.
Indeed, the "Great Rotation" may actually be happening within fixed income as investors put money into high-yield, investment-grade and emerging-market bonds, according to Dodd Kittsley, BlackRock's head of exchange product research.
"There's a clear preference where investors are favoring credit over duration," he told CNBC's "Fast Money."
That doesn't preclude a case for equities. Robert Leininger, an equity fund manager at Gabelli, told the that the case for the Great Rotation rests partly on the fact that the S&P 500 dividend yield is above the 2 percent yield on the 10-year U.S. Treasury note.
He said that individual investors are starting to get back into ETFs and that what individual investors have sold off in terms of their stock holdings, corporate America has bought back in terms of buybacks. (Read More: Bogle: '100% Return' on Stocks in a Decade)
The Great Rotation will happen, Leininger said, "I'm not sure when."