This suggestion has been closed automatically because it did not receive enough votes over an extended period of time. If you wish to see this, please search for an open suggestion and, if you don't find any, post a new one.
There are numerous tasks ahead and importers are amongst those tasks. Of course we will need to evaluate developing importers according to demand.
(Edit) Of course there is always what Ian said!
Im sure their will be importers for all the main forum boards, even if its not a system released by XenForo like ImpEx, individual coding sites will provide them, just give it some time (oh and wait for a release )