I was wondering when someone would do a video dissection.

Some things that AI didn't point out:
- At 1:01 when the mine goes off, the flying debris from the ice hurts the damsel.
- At 1:02 Spelunky Man throws the bomb into the water and it opens a chest and at 1:48 the fallen red bag smashes open a crate.
- At 1:22 Spelunky Man picks up what appears to be the Book of the Dead (design copied from Evil Dead 2?) and it summons red skeletons. My guess is that the skeletons are friendlies.
- The blue player at 1:31 is hurt by a sleeping bat. It appears as if bats are slower to aggro.
- There is a chunk of what appears to be jungle terrain at 1:35 in the temple area. Could this possibly be a custom level?
- At 1:42, Spelunky Man picks up a knife which doesn't appear on his character, but rather as a piece of equipment showing up on his HUD. This does not appear to be the case for all weapons judging from the alien blaster weapon at 1:14 and the familiar shotgun at 1:25.
- An icicle falls from above at 1:14.
- At 1:49 a seemingly new gun comes out of a smashed crate by the red player.
- At the end of the teaser, a Meat Boy character (following the style in
this picture) appears on screen. This is most likely a secret/unlockable character and a homage to Team Meat's use of Spelunky in Super Meat Boy. This leaves the possibility for other secret characters as well (?).
Multiplayer:
- Only Spelunky Man is followed by the camera in the larger levels while other characters can be off screen (1:39). Either player 1 has been designated as or is by default the camera-followed-guy.
- Throughout the multiplayer demonstration, you notice that dead characters drop colored bags. I'm assuming that these bags contain any bombs, ropes and other items the dead character held.