In an effort to appeal to more gamers, APB might get a lot more content in the future, but it's only a possibility right now.
APB's upcoming content has been wondered about ever since it was announced that the game was going to come back on as a free-to-play MMO under the the guidance of GamersFirst. A recent post on the company's APB blog has revealed that players might have a lot more story and a single-player campaign to look forward to in the future.
The company's COO/CTO, Bjorn Book-Larsson, revealed the following information via the APB Reloaded blog:
APB actually has the beginnings of a lot of the elements that will make it a really successful game in the long term, and could in theory exploit (maybe complete) both types of interactions [story and shooter elements]; there is actually a giant backstory to the entire city (100 plus pages of it), there are deep anthologies of the various factions in the city, and there is even the foundation for a single-player mission mode.
Of course, this is all speculative at the moment, but providing some new content that might appeal to a larger number of gamers certainly makes sense. That said, Massively points out that MMO players may not care about the story, since "Global Agenda is a similar title with a fairly deep backstory (and one that is summarily ignored by 99.9% of the players fragging it up in AvA and merc matches)." Personally, I'd rather have the story and the single-player option, but that's just me.