OK it's official the developer beta is out.
The rest of this year will be about moving from VBulletin over to it.
It's going to be a contentious issue for people on XenForo 1.xx versions as all add ons will need to be re written to run on the 2.x versions.
My hope is that by the time we have our ducks in a row to migrate over (winter this year or early 2018?) 3rd party XF add on developers will have upgraded all their "must have" / popular add ons for v2.x
It will be interesting to watch forums on XF v1.0. Many will want to stick on it for an easy life but the XenForo developers are very pro active and I suspect new and cool functionality will likely only be added to The 2.0 version and folks remaining behind on the old version will start to miss out and gradually the movement to v2.x will pick up pace.