According to stats of the AMS-IX, the Amsterdam Internet Exchange (one of the bigger global internet exchanges), the current volume of IPv6 traffic they're processing is around 1 Gbit/s average (graph), on a average total traffic (IPv4 + IPv6) of 436 Gbit/s (graph).
So, traffic levels are still at about 0.23% of IPv4. In the past year IPv6 traffic through AMS-IX has increased about 1000%, but there's still a long way to go.
My medium-sized webdev company has deployed IPv6 locally and remotely. Locally through a SixXs provided tunnel and subnet, and remotely through native IPv6 provided by our hosting provider. In my experience, a lot of companies are working on it, and will help you if you ask them.
It's quite easy, once you know how IPv6 works, to deploy it. The big problem is the chicken and egg dilemma, and convincing management to let you deploy it. I'm glad my company allowed me to spend time on it. I was able to convince them that as a webdev company we need to be 'enablers' and be ready for upcoming technologies. Therefore, to push IPv6 now allows us to work out the kinks before our customers start asking.