No question he's not young, but I'd guess him to be 3.5. He could be a really nice 2.5, but my money would be on 3.5. Its hard to tell on one picture, because you can't see the tines as well, nor get an idea how far out those beams grow.
I don't think he has great tine length...the brow tines and g-3s not stellar from what you see on this view. Tine length is what really cranks up the score, imo. Here's how I'd guess him: spread -17" beams -23", G-1 - 3", G-2 - 9", G-3 - 6". Say he averages 4" on the circumferences. Add that up and I guess him to be 131 gross. Its hard for 8 pointers to score high. In any case...he's a dandy looking buck. I'd probably pass on him early in the season looking for a bigger one. But later in the year, I'd find it hard to pass up a book buck.
Anyway, good luck. Go get him and find out for sure! He's a nice looking buck.