The device charges up, and flings you to specific locations around Blade's Edge Mountains: Jagged Ridge, Singing Ridge, Razaan's Landing, Ruuan Weald. You cannot use the Capacitorium for 3 minutes after landing, while you wait for the residual charge to dissipate.
Some of these quests require other quests to have been completed as prerequisites.
Once you have completed one of these quests, you can talk to Rally and take the flight again. It has also been mentioned that a druid can shift to flight form during the flight, and a mage can blink during the flight.
The Zephyrium Capacitorium consumes a lot of power. Toshley asks you to undertake several tasks to keep the station powered. These quests eventually lead to startling revelations about the Ethereals at Razaan's Landing.