As we noted last week, some analysts think conditions are ripe for more M&A activity.  So we may be seeing a lot of coverage of new deals.  But it is worth remembering that there have been some significant mergers and acquisitions during the recession and slow recovery.  One of the big deals in the drug industry last year was Roche Holding's taking over Genentech.  The two companies had been linked, with Roche owning a majority of Genentech for almost 20 years.  Still, Roche's decision to take full ownership had a significant impact on how workers functioned.  There were new areas where tasks overlapped, and some of the internal competitiveness had the potential to slow things down.  Steve Krognes was a Roche Holding executive who became senior vice president and CFO of Genentech after the two merged.  He recently discussed the merger at Wharton San Francisco, and he gave great detail about hist and others' efforts to create one strong, efficient company a year after the merger: