On the pages I missed during my night, there was some speculation about Miranda's story and how it will continue in ME3. Here's a bit of speculation of my own:
I think her story will feature one major personal conflict, and possibly another connected to the main plot.
The personal conflict will appear regardless of whether Miranda resigns from Cerberus at the end of ME2, simply because that's easier to do, which means it will probably be about family matters again. Whether Shepard works for Cerberus in ME3 or not will be irrelevant, because he, and not Cerberus as such, is around her most of the time and will be in a position to help her deal with it (or possibly have an optional decision path not to do so). In this conflict, her own stance with regard to Cerberus will also be largely irrelevant. Shepard will be able to influence her decisions again, and maybe her personality will change somewhat in the process.
With regard to the main plot, Miranda will possibly follow Shepard's decisions if they have a relationship. If Shepard continues to work on a Cerberus-compatible agenda, Miranda also will, since I think Cerberus' agenda is still something she would approve of, if not their methods. Otherwise, I have no idea where things will go. If Shepard and Miranda are not in a relationship, it's possible that they will come into conflict.
That's pretty much it for now.