This was a great message—whether you missed emails about your grand kids or were debilitated by the IMAP breakdown, the CEO told you what was up.
There will be more fallout from this. Yahoo is navigating a dicey renaissance—about the only thing you could point to as a success for Yahoo in the last ten years was reliable email service. So this will hurt. But how can you argue with Mayer's concise, honest assessment and apology?