Starts bad, ends good, balancing out to... eh.
I picked up Supergirl #1 mostly because of the good reviews I read here on Comicvine. Generally I read that she crashed on Earth and that it was an emotionally touching issue where she felt alone in an unfamiliar world. That sounded like a great character driven story that I want to read.
What I got was something that started with a number of things that annoyed the hell out of me.
Supergirl arrives in(?) as(?) a meteorite in Siberia - but they couldn't have her just crash in Siberia... oh, no... she crashes in the vicinity of Kansas, falls through the entire Earth - and comes out the other side in Siberia where she stops crashing at about surface level. O.K., guess we already know she's more powerful than even Superman who was stopped by a runaway train in Action#1... pfft Kara can travel unscathed through the molten core of the Earth!
Then in the splash page we see her standing in the midst of what is described as "a blizzard", but in actuality seems to resemble a snowball fight with God, as giant balls of snow bigger than Kara's head fall all around her.
And then she's attacked by a bunch of guys in power armor... because, you know, there has to be a fight scene.
Then there's the convenient fact that the power armor guys just happen to come fully equipped with weapons capable of taking out Supergirl (or at least hurting her as she herself tells us) - and remember that's weapons powerful enough to hurt a girl who just traveled through the inner core with a temperature equivalent to oh... about the temperature of the f-ing sun!
Things get a lot better from there - she (thankfully) doesn't speak English, and she has to deal with the mechanical gnats plaguing her while all her powers begin to manifest themselves... including one amusing scene where she hears, among other things, dialogue from other D.C. #1 issues which seems to indicate they are all happening simultaneously.
But none of the good that follows can really make up for the bad that came before... which in the end balances out to a pretty average comic.