Initial impressions time!
I pulled the trigger on a white PS4 bundle, so had no experience with the Beta/Alpha and haven't been following info on the game religiously. I have a decent level of experience with all Bungie Halo games in campaign/multiplayer.
It looks great and has pretty compelling art direction. Technically very solid, nice design all round. Music is good. The movement and gunplay feel a lot like Halo to me, which is a very good things because I love that aspect of Halo. Looking forward to messing around with different guns/powers. I think they really nailed the combat in this game, which is probably the most important thing to me so I'll keep having fun.
On the flipside, I really feel like the game would have benefited from 1 or 2 more locations. 4 locations is pretty slim no matter how you look at it. A bit of mission variety wouldn't go astray, but I don't mind the more piece meal nature of each individual mission. Makes is easier to just jump in for a mission and jump out when you're done.
In terms of the story.... I actually don't mind the approach! I know people are disappointed, and I can understand that. But personally I thought the story telling on Halo 2 and 3 was awful. The original Halo was solid because it wasn't over reaching. Halo 2 was a total convoluted cheese fest and Halo 3 barely even tried. So I guess I like the universes Bungie creates but don't care for the stories or characters very much.
I also feel like people are misrepresenting the Halo games to an extent when talking about combat. Someone said "every encounter with the Covenant felt unique" but I don't really buy that. There was a decent amount of level variety in the Halo games, and some unique encounters. But a lot of it boiled down to mowing down groups of the same half a dozen enemiey types using the same tactics in similarly designed environments.
I haven't jumped in to PvP yet, but this will be the real factor that determines how long I'm platying for. I played Halo 1, 2 ,3 multiplayer for years each. They all had their strenghts and weaknesses, and I'm interested to see how Destiny feels to me competetively.
I'd say it's a solid 8 for me so far.