Waiting for the return has been a hot-and-cold affair. In this year's Q1, sector volumes rose 15% year-over-year -- then leveled off, with the overall first half coming in flat, and things staying quiet in the face of the recent volatility in the financial markets. While there's now "a lot more caution in this sector," though, he sees a second wave developing, spurred by foreign companies moving to acquire the U.S. companies they expect to benefit from increased infrastructure spending lying ahead.

Across the wider M&A horizon, Morrissey's expectations are being heard more and more in recent weeks, in part reflecting the solid growth that at year-end seemed almost inexorable.

Globally, over 21,000 deals were announced in 2010, worth more than $1.9 trillion in total, according to Bloomberg News research. That represented a 12% increase over 2009, and a sharp reversal in the two-year decline that began in 2008. Further, a Bloomberg report last December showed "tempered optimism" on the part of over 1,000 financial market professionals for continued growth of dealmaking in 2011.

The optimism certainly seemed warranted as 2011 began, with mega deals such as propelling things. So when deal volumes seemed to peter out in Q2 -- with announced M&A totaling $611 billion, off 23 % from Q1 -- many saw it as temporary. And they have been expecting other sectors to begin catching up with technology, where deals like and have set a steady pace.