Im Forum von Dropbox findet sich der offizielle Eintrag der Entwickler zur neuen Version:
Introducing a shiny new feature: a new tray popup that combines the old tray menu features with a timeline of the most important sharing events in your Dropbox. For instance, if someone shares a link with you, you can now see it immediately! Moreover, if someone shares a folder with you, you can now accept or decline the invitation directly from your desktop. Not only are you notified of these events in real time, but you can easily get to them later. Also, files recently edited are made available so you can easily view or share them.
Via TUAW
Noch mehr Apfeltalk
Neue Forenthemen
Systemmitteilung