Order of no particular importance:

*** Add new callback for status ***
TimeRemaining()

*** the backends will have repo controls ***
Add the callback and methods in PkBackend
Add details to the help file
Add methods and signals to the client library

*** Prepare download to refresh system ***
Either use a flag or a new method. I'm not sure which yet.

*** Add a way to import GPG keys ***
In fedora, if you add a signed repo you have to agree to the GPG key.

*** Split up PolicyKit install into different types ***
Have different permissions for signed and unsigned repos.

*** Handle rollbacks for select backends ***
To do rollbacks sanely in PK we need a few things:
 * allow transaction data to be changed in _db