Broken Base: Some people find the Mood Whiplash between the comedy and tragedy of the film too much to take. Others think it fits perfectly and find it a great film. It has a 55% review on Rotten Tomatoes.
Everyone partying it up before the end of the world. Patton Oswalt's character reveling in the loose sex he's been having since the reports is the cherry on top.
The whole Friendsy's scene. Everyone looks like a bunch of ravers (and are even rolling on ecstasy or getting stoned) and just accepting anyone that's coming in.
The random guy in the police station, wearing a sandwich board proclaiming the end is nigh. Dodge calls him "a peaceful, validated man."
Dodge returning home after being on the road for about a week and finding his housekeeper Elsa still there, cleaning as if it's not the last day before the end of the world. Dodge's reaction: "Are you shitting me?!" Doubles as sort of a Heartwarming moment, since Elsa considers Dodge her friend and continues to work, whether or not she is aware of what's been going on.
Can double as a tearjerker as no one in a civilized society wouldn't know what was happening. People cope with situations different ways and for Elsa that is treating everyday like there will be a tomorrow. The alternative for her may just be too much for her to stand.
The silent nod between Dodge and his father as he puts Penny on the plane.
Dodge comforting Penny at the end as the asteroid nears.
The first loud noise from the impact, and Penny's face when its heard.
"Elsa?! Why are you still here? GO HOME!"
That part is even worse when you understand that Elsa is pleading with him in Spanish because she considers Dodge her friend.
The TV anchor signing off and saying "God bless you all."
The ultimate Fridge Horror with each "Last..." thing shown is how everything in civilization is slowly stopping, being ground to a halt. No more publications, or music, or new things. All of the children/infants seen in the film? Their lives are over before even beginning. Many of them won't even be fully aware of what's happening.