AFAIK he never said that it will be free to play.
Only interview I read (and I read a few) that he answered business model question , he stated that it was not decided yet and they are open for all possibiliteis.
Here is a link to this interview with Jake Song. So no it is not F2P , not P2P , is is To be Decided.
Also mmorpg.com has ArcheAge correctly labeled as TBA or n/a.
MMOSite has it wrongly labeled as f2p , no other major website has it labeled like that.
With ArcheAge beign complex as it is I think it will be better for gameplay if it is p2p tbh.