A total of 79 mergers and acquisitions raised $4.3 billion in the second quarter of 2010, according to a report by Dow Jones VentureSource. That’s a slight 4 percent drop from last year’s report. Overall, this year is slightly up, 12%.

The largest deal by far this past quarter was Google’s $750 million acquisition of AdMob, the large mobile advertising network.

Separately, the National Venture Capital Association counted 92 deals with a total disclosed value of $2.9 billion in a report of its own. The table below shows how far off today’s M&A market is from the booming days of 2006, when it seemed like Google bought everyone.

Both NVCA and VentureSource also reported that IPOs were numerically up, but financially shaky, in the second quarter.