For your reading benefit I've quoted this post into sections with titles.
If Bungie Aerospace isn't a game, why is it in the list of games?
Bungie and Activision? Could this mean Subscription-exclusive content?
If Activision is now going to publish Bungie Studio's video games, does that mean they will try to incorporate exclusive online features similar to what Call of Duty Elite is providing for the Call of Duty franchise's future installments?
Bungie's next franchise, if you hover your cursor over the 'Games' tab on the navigation bar above, it's called 'Bungie Aerospace' rather than the "[insert franchise] Universe".
'Bungie Aerospace' suggests an MMO
Now this could be due to the franchise's name not being revealed yet, but what if Bungie Aerospace is simply a series of DLC installments?
Bungie has done pretty well releasing a game per year. Look at Halo 3: ODST and Halo: Reach. If Bungie has that game-per-year quality, and Activision wants people to subscribe to their cool online features and exclusive content, then product consumers will be forced, or greatly encouraged, to subscribe to the extent that the content is required for standard gameplay.
Aerospace may be a series of solar systems or areas in Bungie Aerospace where players can roam on planets and have battles in an FPS MMO, apparently called Destiny and code-named 'Tiger'.
Every several months, Bungie Studios will produce a new installment, and a side-order of Activision subscription-based content that everybody else wants, which is basically a long line of DLC content to add to the online MMO.
To sum this all up...
It's like the Halo Universe, Halo 3 for example, but every 3-4 months a new area of space will be added to the MMO.
It could even be like World of Warcraft - in space!
Every 3 months down the line a new chunk of Bungie's Aerospace will be added to the giant MMO world map. And bit by bit they will create a giant area of their own universe.
TL;DR:
Bungie + Activision = subscription-exclusive content, 'Bungie Aerospace' suggests monthly releases of an area of the aerospace itself like World of Warcraft only an area of a map is added every so often.
Thoughts, Bungie.net Community?
[Edited on 08.04.2011 3:45 PM PDT]