It's a great year for Murray: Olympic gold + 1 slam. (Beats his usual 2 master titles a year for sure!). No offense to Murray fans but the USO win was a bit lucky because Nole got screwed by the schedule and came up short physically in the 5th and also because he avoided Fed. Murray is a great player but he's not in the same league as the big 3 achievement-wise. And he may never be. His other problem is that, unlike the other top 3, he has a poor record on clay. He's more specialized in fast surfaces. He's also not as solid mentally imo.
I still think he'll win Wimbledon one day.