The $45B acquisition of Yahoo! by Microsoft will probably go through and the broader implications aren't just about search and advertising. If Microsoft uses up its war chest on this one big bet, it is on consumer markets to find its next cash cow. This of course will not have a short term impact on its enterprise business, but it does say something about its relative future.
While people are quietly mourning the implications for Silicon Valley, I actually think this move will open up new spaces for startups, although reducing some of the acquisition demand. Others are mourning the implications for Yahoo's open source projects. But I have to wonder if there is an upside of cultural injection.
Overall, this was Ballmer's way to give an answer to the Street for the one repeated question that drove him nuts. Now I wonder if Google is feeling lucky. And the same question for enterprise software giants.