Apple retail employees are not allowed to share work related information online. Some do it though anonymously.
Apple's treatment of their retail employees raises eyebrows since a while. Apple customers get great support, but behind the scenes there are policies and management practices that put a lot of pressure on employees. Some use social networks as outlets of their frustration, which is of course against Apple's policy and can get you fired right away. This is why these employees share with an anonymous account and have to fear that the "Apple police" finds them.
9to5Mac has just published a lengthy piece that reveals some of the most active (former) Apple retail employees. The profile contains many ancedotes from the Genius Bar and other insights in the secret Apple retail world.