Unless you have been sleeping in the outer herbrides with no access to the internet, then you would have known that vSphere 5.5 was announced at VMworld.
It has been a few weeks since San Francisco and anticipation on the general availability on vSphere 5.5 has been high. However the good news is the wait is over, it is here.
To obtain vSphere 5.5 login here and enjoy the next release of the worlds most popular hypervisor.
VMFocus 
Can i use my current license 5.1 for 5.5?
Hi Alexey, yes you can.