American Slang was the first song of the Gas Light Anthem I heard and I instantly liked it. They're a different type of rock that i'd listen to normally and a breath of fresh air. The song has a very catchy riff to it and the lyrics are strong.
If I was to describe how good each song was then i'd just be typing the same things. I can't pick which song is the weakest.
One thing about the album as a whole though is, it only has 10 songs which is shorter than a standard album nowadays and only one song actually exceeds 4 minutes long. So yeah, it is quite a short album. But HEY! It's the quality that matters, not length.