I would say dev only at this stage since it's not even in beta. It's up to you of course ;)
V1 is stable and works especially well for small to medium forums. Of course, there will be an upgrade path from v1 to v2, so I'd say it's worth jumping into v1 now even if you're thinking about going to v2 some time in the future.
Vanilla 1.2 is just around the corner and is bringing some pretty exciting improvements to the table!