Aquisition Time

I had heard that one big sign of the economic downturn was that mergers and acquisitions activity had dwindled to nothing as firms with cash moved to hoard it and firms without cash found it difficult to borrow on attractive terms. But now today in the paper I see that Oracle is buying Sun, Pepsi is offering $6 billion to buy the main Pepsi bottlers, and GlaxoSmithKline is buying Stiefel Laboratories for $2.9 billion.

Has something changed, objectively, to make M&A activity more attractive than it was a month ago?