1:20 The editing is a little odd (it goes directly from this to Hal flying) but this looks like a ship blasting off from Oa. Traditionally, Abin Sur is depicted preferring to travel in an armed ship out of paranoia about his ring's effectiveness, so this could be that.
1:21- 1:26 Cool Ring Thing #1: You can fly through space without dying, courtesy of a force field. The early CGI is pretty dodgy here, but I'm liking how big the space stuff looks - for this to work as more than just another superhero movie (particularly as this is opening between Thor and Captain America) it must emphasize the cosmic, Star Wars-level bigness of its world. Speaking of which...
1:27 Oa, homeworld of the Guardians, central headquarters for the Green Lantern Corps.
1:28 Green Lantern fans in the theater with you are/were applauding because the Chicken/Fish/Lizard Man on the left is Tomar Re, Jordan's (eventual) good buddy and Green Lantern of Sector 2813. Tomar isn't just important in the Green Lantern mythos, he plays a pivotal role in the larger DC Universe; he lives with the shame of being unable (though not for lack of trying) to prevent the destruction of one of 2813's key planets - Krypton.
1:29 Our first look at Mark Strong as Sinestro, a character I never would've expected to see looking exactly like he's supposed to in a movie. This is another character who, if they follow the books, will eventually turn evil (first clue: his name is Sinestro) and join with the Guardian's enemies to procure a Yellow Ring (in the Green Lantern mythos, the whole chromatic spectrum has corresponding powers and yellow is "bad") but he typically starts off as a mentor whom Hal rebukes for being, essentially, a Bad Cop.
Incidentally, most of the aliens are mo-cap CGI creations, but no one is actually wearing a Green Lantern suit in this - Reynolds and company filmed their scenes in computer-friendly body stockings, and the costumes were painted on with CGI after the fact. Really.
1:31 - 1:37 Bouncy Jeep passenger looks to be Thomoas Kalmaku, an aircraft engineer of Inuit descent who serves as Hal's obligatory "one friend who knows my secret identity" guy. In the early comics his nickname was "Pie Face", as in "Eskimo Pie." For obvious reasons, they don't do that anymore.
1:42 Our first look at how the Ring's constructs work - Hal slams some thugs away with a ginormous green energy-fist. Looks cool, but hopefully more interesting constructs are awaiting.
1:45 Peter Sarsgaard as Hector Hammond, probably the main villain of the piece. Supposedly he has a new, streamlined origin for the movie, but originally he's a petty crook who becomes a bulging-brained supervillain after exposure to a radioactive meteorite (I bet it'll be the remains of Abin Sur and/or his ship in the movie.) That thing he's coming out of looks like the same "bubble" from 1:14, so maybe that was actually him.
1:50 And the fandom rejoices again. Kilowog, the lovable bruiser of the Green Lantern Corps and a major fan-favorite character, looking more-or-less like he should.
1:52 Hector Hammond again, now much more severely mutated. He looks ridiculous, and I love it. I'm not 100% sold on the design specifics of a lot of this, but I'm psyched at how much they've gone for it when it comes to the 1950s pulp-sci fi feel of the general Green Lantern mythos. Big-Head Hammond looks like something out of the original 60s Star Trek, which is as it should be.