The new release has a smaller file size [58mb] and has a number of new features.
I recently installed v5.8 on Windows 10 Technical preview. It required .Net 2,3 feature to be enabled.
The latest version works with .Net 4.5 so no need to enable .net 3 feature.
Quicker simpler install…
Blog Post:
http://blogs.vmware.com/PowerCLI/2015/03/powercli-6-0-r1-now-generally-available.html
Release notes:
https://www.vmware.com/support/developer/PowerCLI/PowerCLI60R1/powercli60r1-releasenotes.html