OK, here's my update after spending a couple of hours with this.
Intro/Tutorial/Story
The character creation is intentionally sparse, to get you into the game more quickly. The only time you ever get to see your character is at the Tower (social hub) anyway, so it doesn't really matter. The tutorials are also seamlessly integrated into the first couple of missions. It's really quite non-intrusive, and allows you to pick up the gameplay fundamentals with ease while you play.
The story's really cool so far, although like most shooters, I expect it to be quite short and really just a means of introducing the various weapons and maps/settings. One thing I really like is that you'll occasionally see other people going about their own business. You can play through the story multiplayer, too. I couldn't really tell if it scales up the difficulty to compensate.
Multiplayer
The competitive multiplayer is fairly standard for this kind of game. Character level doesn't matter. All stats are leveled out, and even the weapons are leveled out, so a normal shotgun will do the same damage as a legendary shotgun. The only bonuses that are retained are character and weapon perks. For example, if you're high enough level to have a bonus effect on your super move, you get to keep that in PvP. If you have a weapon that has a little "bonus ammo" or "improved aim" slot, you'll get to benefit from that. So park of the game becomes about managing which weapons will work well in PvP (valuing perk slots over sheer stats).
There are some really nice user experience features that I noticed. I'm not a big shooter player so I don't know how much of this is standard / incorporated by other games, but one thing I really liked was that the game has separate voice channels for your fireteam (your friends who have joined you in a room and follow you from game to game) and for the rest of your team. So if you're paired up with someone you know, and together you enter a 6v6 match, you can toggle between talking just to your friend, or to your whole team. The game also incorporates a clan/tag system directly within the game, to make it easy to group up (this is probably more standard by now, but I've played games where you had to do all that stuff offline).
On the UX front, I'd be remiss if I didn't mention Bungie's site. They have a comprehensive
Destiny companion on the site that makes it totally worth signing up for. As a bonus, you don't need to worry about managing a whole separate account—you can sign in directly with your Microsoft or PSN accounts. This site gives you all the current information about all your characters (gear, current bounties, missions completed, comprehensive stats & history), lets you know when you have messages, etc.
This is my basic profile.
Loot & Progress Hooks
Progress curves up nicely, at least in the early game (I've heard there are some major walls later in the game, but I'm not there yet). You have the typical incentives like common, uncommon, rare, and legendary gear. There are also crafting materials that I think you need for creating legendary gear.
In addition to story missions, there are also side-quests that you can fulfill in the open-world "patrol" maps, specific bounties that you get rewards for completing (e.g. kill 30 enemies with melee attacks)—you can carry ten of these at a time—, daily & weekly strike/raid/community events that trigger on certain maps at certain times and usually require a team to complete for certain rewards, and big game-wide macro-bonuses that you can strive for which mainly just promote long-term play (e.g. kill 5000 of a certain type of enemy to unlock a permanent bonus to the $ they'll drop).
This stuff can all be tracked in the
Destiny companion on the site. (I believe they have an app, too.)
I'm looking forward to sinking some more time into this. It doesn't feel like an MMO, and it doesn't even really feel like
Borderlands. The story mode feels more like an adventure game, but the rest of the gameplay definitely feels like a familiar FPS, especially if you've played
Halo. I think it'll be really fun to play when we can put a clan together and start doing missions with a few people.