At least on the Mac it installs LR CC besides LR5.7 -- so maybe you're just seeing the wrong link (happened to me)
As tlieser, says you're probably opening the old version as both are now on your system.
On one of my installations there was no new shortcut created and I had to go and find the program and create a shortcut. Clicking the old shortcut brought up 5.71 as with you. I'm on Windows 7 so looks like it's happening on both Windows and Mac.