At least part of it is set in Boston
Fallout 4 was rumored to take place in Boston, and it looks it will be, at least in part, based on some telling imagery in the trailer.
In the photo below you can see the Bunker Hill Monument. Not to be confused with the similar-looking Washington Monument used in Fallout 3, this monument proves that while we might not be starting in the Capital Wasteland, we won't be too far away from it. We get a glimpse of the State House too.
We might play a bit of story before the apocalypse
Much of the trailer jumps between before and after the apocalypse, suggesting we'll get a better look at the world before the bombs dropped.
It'd be interesting if Bethesda let us play through those final moments, potentially entering Vault 111 as one character and emerging as another (a descendant, perhaps?)
Plenty of familiar faces are back
There's plenty to see in the way of vistas and characters, including Protectron (or a newer version of it) which makes a cameo in an industrial setting. Friend? Foe? Who knows, but it's got its little blaster aimed right at you.
And then - oh God - Deathclaw, everyone's most feared opponent, is back and ready to troll you hard.
In Fallout 3, reaching Deathclaw meant that you had made your way pretty far into the game, but not even a group of heavy artillery-toting militants were as difficult as taking on a single Deathclaw.
There's a talking protagonist
POTENTIALLY CONTROVERSIAL MOVE KLAXON: at the end of the trailer the vault dweller does the unthinkable and actually SPEAKS WORDS with a "Let's go, pal" to his dog. Well, we're pretty sure it's him - we don't see his lips move - and not the dog.
Giving a voice to the main character isn't something we expected Bethesda to do, unless we'll actually be playing as a mutant dog that's mastered the ability to communicate telepathically.
More importantly, he's wearing a Pip-Boy! He's also emerged from Vault 111, though we expect it won't be the experimental Vault 111 described here, where occupants had to live in an eternal Christmas.
Expect plenty more of those old-timey hits
The trailer opens with the familiar four bars of The Ink Spots, this time going into It's All Over But The Crying.
Expect Fallout 4 to continue the trend of borrowing vintage sounds from 1940s America. We also expect Galaxy News Radio anchor Three Dog to make a return after the voice actor dropped several hints on Twitter. If you look at the 2 minute mark, you'll see a GNN logo - Galaxy News Network?
The dog is back, but please don't kill it
Dogmeat was a decent companion in Fallout 3, but the dog didn't add an awful lot to the story.
However, in the Fallout 4 trailer, much was focused solely on the dog in the post-apocalyptic world. With that, one might assume that the dog is as central to the plot as the human protagonist.
But please, for the love of Nuka-Cola, don't let this dog die.
The Wasteland Ghouls get scarier
We can expect that the usual enemies will populate this post-apocalyptic world, though we're hoping that Bloatflies were left on the cutting-room floor this time.
Judging from the looks of this trailer, Ghouls, those zombie-looking humanoids, will be back, but with some new traits that make them scarier than ever. They run terrifyingly fast, pushing objects out of their paths, and look to be suited with armour. Let's just hope that the protagonist is packing just the right weapon to put them back in the ground.
The secret ingredient that made Fallout 3 so sweet compared to Bethesda's other FPS titles was V.A.T.S., a strategic element of gameplay that allowed you to gib the living hell out of your opponents.
We didn't see even a hint of it in the trailer, but you can be sure that Bethesda will have something more to say about it come time for E3 2015.
Mysterious, morally-questionable characters aplenty
Fallout 3 had a bunch of memorable characters, from Mister Burke to Three Dog and The AntAgonizer. The quality that tied them all together is that they put the player into murky water, morally speaking, by asking them to make decisions about the fate of others. These quests are why Bethesda games have a legacy.
Who's this dude, then?
It will miss the old-gen consoles
Despite the fact there's a pre-order section on the site, Bethesda hasn't confirmed a release date - but has confirmed it's only coming to PS4, Xbox One and PC. Furthermore, the linked retailers don't seem to have their orders live, so who knows what's going on?
Bethesda might be waiting until E3, where we'll get a world premiere of the game in action, to confirm when it will be available. Fingers crossed for 2015.