peHUB Second Opinion 5.17

So, did Yahoo just buy the social blogging site Tumblr? We may find out on Monday.

The IPOs of business software companies Tableau Software and Marketo both soared today, as expected.

SAC says it’s done cooperating with federal securities regulators.

Morgan Stanley has a happy Facebook anniversary.

Meanwhile, Mark Zuckerberg’s shares in Facebook are worth roughly $6 billion less than they were a year ago.

Former Groupon CEO Andrew Mason has recorded a musical album that imparts business lessons. (This, we have to hear.)

A drop in European takeovers has depressed global M&A activity, but bankers see activity picking up.

Sean Parker may have wedding permit problems.

The Sacramento Kings aren’t going anywhere.

How Google beat Apple to a streaming music service.

Photo: Facebook CEO Mark Zuckerberg delivers his keynote address at the Facebook f8 Developers Conference in San Francisco, California September 22, 2011. REUTERS/Robert Galbraith.