IPv6 is to be IPv4's successor. With more encreasing devices that needs to be connected to the internet it will IPv6 to accomodate all the needed addresses.
We most commonly use IPv4 the first version of internet protocol to be internationally deployed for addressing. The news is that IPv4 is running out of addresses so Internet Engineering Task Force (IETF) developed a revision IPv6 (Internet Protocol version 6).
IPv6 has a larger address space it has a 128-bit addresses allowing for 2^128, or approximately 3.4×10^38 addresses which is more than IPv4 32-bit addresses, allowing for only 4,294,967,296 unique addresses worldwide. IPv6 addresses will look something like this
compared to 192.168.1.1 of IPv4
Some major advantages of IPv6 is stateless address auto configuration (SLAAC) which is the automatically configure of hosts when connected to a routed IPv6 network using the Neighbor Discovery Protocol. Multicasting which is a transmission of a packet to multiple destinations in a single send command. Network-layer security which is Internet Protocol Security (IPsec).
IPv6 just launched last 06 june 2012. Since most companies who sell products like routers and internet providers still use IPv4 it will take some time for the transition and some time to getting used to.
So since IPv6 has a large address space it will be providing internet addresses for a very long time.