Silver Lake has just announced it will acquire Serena, a San Mateo software provider that helps companies cope with technology changes, for $1.2 billion.

That’s nicely over the current market valuation of $972 million (valid of this writing). But it also fits a pattern of large software acquisitions by Silver Lake lately, suggesting they actually do have a plan for all of this. Silver Lake has aggressively led…

the tech buyout boom, with the recent record $11.3 billion acquisition of software company Sungard, and before that, the $2.05 billion acquisition of UGS, at the time the largest private investment into a technology company.

Now you know why Roger McNamee felt he had to leave Silver Lake to do his own thing. He helped launch Silver Lake back in 1999, but then left over a year ago to pursue his passion, which is the consumer media and entertainment area. He just couldn’t get worked up about these enterprise software deals, he told us. Now that both sides are clear in their vision, it seems both are executing on all cylinders.

UPDATE: Corrected reference above to UGS.