It's a great game that builds on many successful ideas of recent games (The hunting from RDR, the exploration and viewpoints from AC and so on) but no one seems to mention the awful pacing on the game.
The first island is nicely paced and ends well, and could wrap up there and then, but then it throws you over to the next island for a very short repeat of the first and ends on such a weird note.
Within 20 hours I had:
Crafted everything (which can be done completely on the first island)
Unlocked all signature weapons
Owned all regular weapons via radio stations/ bought attachments
Collected just under half the relics and half the letters
Completed just under half of the hunting quests and most wanted
MAXED OUT MY SKILL TREE (way before the end of the game)
Completed the story
Now tell me, after 20 hours of doing that, what point is there to complete the rest when, one, money is now useless, and 2, XP goes towards nothing at all. This makes supply drops, races, wanted dead and hunting missions pointless. One of the main things for money to go towards is weapons, but, you can unlock every single weapon for free via radio towers. The skills were also strangely tied into the campaign, so rather than leveling up or completing certain requirements to unlock skills, all you had to do was progress a little further in the story and all of a sudden you can buy every skill available, aside from 3 or 4 skills which required things like "buy 3 bulletproof jackets"... really?
So yes, seems people are forgetting that despite being fun, it really was poorly thought out. It's like they fixed many of the flaws of Far Cry 2 (respawning enemies and bases) but then broke others in the process (meaningful currency and progression).
A good game? Yes.
GOTY? Definitely not.