Okay, the first thing to say about Firecracker is that I really, really enjoyed it. The second thing to say is that it won't be everyone's cup of tea.
The main thing that will put some people off is the MC. Astrid is arrogant, obnoxious, power-crazed, rude, misanthropic and slightly sociopathic and yet, for me, she totally worked as a character. She has no morals whatsoever, but she does have standards. For instance, she has no problem smooshing a Twinkie between her hands and wiping it in the chief bully's hair in the middle of the school cafeteria, but she would never, ever do the same thing to the socially-inept hair-chewing loser. That's not cool.
She does grow as a character as the book progresses, and we find out a little about exactly why she's so very chippy and unpleasant, but she doesn't do a complete personality one-eighty and start wearing a hair shirt for all her past misdeeds. I was glad of this, because I think it would have weakened her as a character. Instead, she develops new ways of looking at life, whilst retaining her hilarious snarkiness.
I liked Astrid and Noah's relationship and the way she lowers her defences a teeny, tiny bit to get to know him but never gets all lovey-dovey. In fact, I just generally liked Noah. He wasn't like a Book Boyfriend or anything but he was exactly the right compliment for Astrid.
The plot isn't anything groundbreaking - it's kind of a classic tale of: loss of something important, gradual adjustment to new circumstances followed by big reveal/betrayal and then a kind of be-careful-what-you-wish-for moral, but the story is interspersed with so many great anecdotes and asides (usually about Bharani princes or shady politicians) that it actually becomes something pretty special.
Another thing that shines the plot up is the writing, which is superb. Iserson has a really cool way of writing that's slightly off-the-wall and yet descriptively spot-on and he can be truly hilarious at times. This book actually had me laughing out loud in that irritating way people do when they're reading a funny book in the company of someone else and the other person keeps asking what's so funny, and the laughing person just goes, 'Oh it's something funny in this book. But it's the context. If I say it out loud it won't sound funny.' That was me, last night, reading this book.
Now, I have to give fair warning: there's a love triangle in Firecracker. But it's such a ridiculous love triangle, that it made me laugh rather than throw the book across the room. I doubt anyone is going to be putting up a Team Pierre icon on the sidebar of their blog.
So, yeah. Firecracker was a really fun read. If you're looking for something serious and profound that rocks your world and makes you question your metaphysical existance, then it may not be the book for you. If you're looking for something to take to the beach and laugh irritatingly at, then you should pick it up.