Web and email servers that are publicly accessible, and your desktop or laptop that you connect at home or at a Wifi point, will probably still be IPv4.
IPv6 will be used internally by large companies, by large DSL ISPs and Comcast, but the interface the end-user will see, will be IPv4.
I think 99% of the usage will occur in non-visible ways - Comcast will have all their home-subscriber modems put out IPv4 on the side you see, but v6 on the pieces you don't, such as the management interface that lets them remotely configure and manage your modem.
Combined with large 6to4 gateways they will run on their edge (where they connect with non-v6 enabled systems), most people will not really notice anything.
The tipping point will come, but not for another 5 years I think, that is, 2 more hardware upgrade generations.
Mobile of course, will go to v6 first, since no-one cares as to how their phone accesses the web.