I get messages from time to time saying I got "promoted" in my career, but I can't figure out what triggers that.
When you go to your charecter screen (click on your portrait/avatar in the main menu), you have an option to view your "career progress". In there you'll notice that you have a progression bar made of several levels for each of the main factions (Eco, Tech & Tycoon). The progress bar is made of ranks represented by circles. Each circle has its own progression bar that is filled by gaining career points for that faction. The messages that you got that you have advanced your career, ment that you have gained enoughf career points with one of the fanctions to gain a new level. Each level gained gives you rewords, avatars for your profiles, more upgrade slots at the arc, colors and formulas for the academy.
You gain career points for accomplishing goals at the main campeign, comptiting the daily quest for a certain faction (the faction that you chose will give you the points), global events, senate votes and maybe for some of the achievments (i.e make so and so quest for that faction).
From what I have read, you get experience from performing certain actions: such as watching a video for the first time should give you 200+ xp per faction or performing a global mission would do the same.
Also, "The gameplay includes 'World Events' - special missions only offered for a limited time, allowing all players to band together and complete the missions. Completing missions will reward players depending on how many people participate."