Number of units sold announcements by companies
The rule of thumb is if you can't announce multi-million sales, you don't say anything.
Apple sells multi-million of everything within segments(Mac, iPhone, iPad, iPod, Apple TV), but they refuse to give breakouts. They don't tell us how many Airport Express devices they sell.
Microsoft happily tells us about Windows & XBox sales, # of SkyDrive documents, Outlook.com active users. But they won't tell us how many Surface RT & Pro they've sold.
Google never tells us anything about products they sell.
Amazon is mum on Kindle sales since day 1.
Samsung proudly tells us how many mega-millions of Galaxy Phones & Notes they've sold, but don't tell us about tablets.
Especially since Apple has redefined "success" in phones & tablets. Even if Microsoft sells 1 million Surface Pros in this quarter they can't tell us because it sounds pathetic compared to iPad sales.