Yeah, I used to think that, then I participated in some IPv6 conversions and watched some others. I don't think that any more. IPv6 may not be the Glorious Solution to All Network Problems Ever, but it's not just the obvious incremental improvement on IPv4 either. It's a new protocol.
(I do sometimes wonder if an IPv4.1 that simply set a flag and used 8 bytes instead of 4 was proposed right now if it could still beat IPv6 out to the field even with IPv6's head start. Note, I'm not saying this would necessarily be a good idea, I just find myself wondering if IPv4.1 could still hypothetically beat IPv6 to deployment.)