Gmail is constantly "updating" their interface and it's driving me crazy. When I signed up for the service I was excited about the simple, clean look and functionality. Since then Gmail has changed its format about a billion times. It seems like every time I log in the buttons are in a different place, and a bunch of new superfluous features have been added.
In my opinion, Gmail is suffering from the same problem that Apple has been experiencing over the last decade. Originally Apple created basic software like iMovie, which made movie editing much easier for the average computer user. Since then they have been gradually complicating the program by adding advanced features. While there is still a vast difference between iMovie and professional video editing programs like Final Cut Pro, Apple is moving away from what made it successful in the first place.
Apple and Gmail, stop while you still can! Keep your software user friendly and clutter free!