As far as 500 million dollars is concerned, idk what Bungie even did with all of it. The only thing I can see is putting money into making it available across all major consoles. Other than that, this is a complete waste of money. The soundtrack is amazing; which is something I always have to give Bungie credit for. Halo's soundtrack was unbelievable and this is still quite impressive. But other than making the game look nice on the newer consoles and the soundtrack, things will get old after playing Destiny for awhile. Peter Dinklage voices your little robot buddy, Ghost, and I have gotta say his voice-overs are cringe-worthy sometimes. His lack of emotion and monotone delivery makes me wanna mute the game sometimes. I have heard that Bungie wanted him to sound that way on purpose... but regardless it takes away from the game.
Basically Destiny incorporates every game imaginable. It touches on Borderlands, Halo, Call of Duty, Assassin's Creed, Star Wars, Mass Effect, and pretty much any game you can think of. This is what I love about the game. As far as a storyline goes, there really isn't one except the fact that our galaxy becomes taken over by enemies known as The Fallen, The Hive, Vex, and a few others that are spread across Earth, the Moon, Venus, Mars (and dlc rumors to have Jupiter or Mercury as of typing this). Your job is to go around wrecking your way through enemies to destroy gigantic evil beasts and shrines and other things. So you basically go through the storyline to rank up til you're level 20. Once you are level 20 you must find, earn, and equip armor that has 'light' in it to get to higher levels; the more light you acquire the higher level you get. There are 5 different types of armor for your head, arms, and feet: common (white), uncommon (green), rare (blue), legendary (purple), and Exotic (yellow/gold). Exotic is the hardest to get (I somehow managed to get my hands on some exotic gauntlets but I was extremely lucky). You also can acquire what is known as Class Armor which is basically a band you wear around your arm indicating you are a part of 1 of 4 clans: Vanguard (default), New Monarchy, Dead Orbit, and one other I can't remember. You pick which you want and xp, and crucible marks are banked there so you can purchase better weapons and armor (such as legendary).
There is multiplayer known as The Crucible. You get a deathmatch, FFA, deathmatch with possible revival and a gametype similar to headquarters on COD but with flags. There is a 5th gametype known as salvage that only is around on particular days. There are three types of character you can be: Titan (bulky and strength oriented), Hunter (fast, knife-wielding), and Warlock (back support and energy). I will say that Crucible is absolutely awful in my opinion. It is extremely Titan-friendly. What is also unfortunate is you need to play multiplayer if you want to rank up at some point. I find this to be, easily, the worst part of Destiny; I won't complain about this too much because you can easily find blogs and comments b****in about this already. I have a feeling Bungie will fix this eventually but as of now expect to get your ass kicked up and down the board. They say it is not level-oriented meaning you have the same chances to kill someone who is level 25 even if you are a 5. This is technically true except as a higher level you have access to better weapons which therefore makes it unfair again.
If you want to rank up from 20 you have to play Vanguard strike missions which is basically 1 of 5 missions: Nexus on Venus Summoning Pits on Moon, Valus Ta'aurc on Mars, beating the Archon Priest on Venus, and Devil's Lair on Earth. Archon Priest is the hardest imo followed by Valus Ta'aurc and then Phogon, The Untamed in Summoning Pits. Now these strike missions are required to rank up and earn good weapons. They are usually quite eventful and very hard to do; HOWEVER, they get EXTREMELY old because you have to grind these 5 missions constantly after level 20. This is why I say it is insanely repetitive.
There are also collectibles: Gold chests and Reviving Dead Ghosts. There are 60 ghosts to find and 5 gold chests on each planet. These keep you busy if you are an achievement person.
You can also join in with other players around the world and you can even be on one mission and cross paths with other people who are on completely separate misses; I find this very cool. You can meet a lot of people doing this. The Tower is basically your 'home' where you go and accept and turn in bounties (side missions you can do), encrypt hidden items, buy weapons, etc.. This is where you can meet a whole lot of people running around which is another way you can meet new people to play with. Overall Destiny is a very fun game to play and I'm still quite addicted to it; but be aware that if you hate repetition and grinding this isn't the game for you.
EDITED REVIEW: As of now, Bungie has patched multiple things that make it harder to rank up once you reach level 20. This is, in my opinion, completely ruining the game for me. I don't take back what I have said prior to this but I will say that Bungie's continued patches are going to make this game much less fun to play if they continue to hinder the grinding process (which is what the game is supposed to be in the first place).
Anyway, hope this helps a little. Keep Gaming!