Flacco was a median-level Qb for the last few years now, and he's made a career off a brilliant postseason run. He could be a good upgrade for some teams looking for a slight upgrade (maybe he goes to Washington or Jacksonville, maybe Miami??). The writing was on the wall when they drafted Jackson. Both sides knew it.
It was great for Baltimore to be able to rejuvenate their team with Jackson in the short-term. They can run the ball and keep their great defense fresher because of it. I like the attitude that Jackson carries, and I think the Ravens just needed some change. They needed to rally around something. They look like a team that's playing with nothing to lose, and it's working in their favor.
I just don't think he's good enough to be a long-term solution in this league. You need to be an accurate thrower to be a successful QB in the NFL long-term, and he simply isn't. Maybe he can get there, but accuracy is a reallllly hard thing to develop at this stage of your football career.
With that said I think they have enough momentum to contend this year, especially when you consider how vulnerable the rest of the AFC is. Only situation I don't give them a chance in is visiting Foxboro.