This was the first Bill Bryson book I ever picked up - and I loved it. He is hysterical, witty, observant, and even profound at times. This is ostensibly a book about Australia, but it's also about the people he meets and how they typify Australia, and just as much about him and his reactions to a foreign country, one he find incomprehensible at times. (And seriously, how can a country just "lose" a prime minister?)
It's not comprehensive - he hits mainly the most well-known and the weirdest points of interest - but to be fair, it's a HUGE country. I do recommend this book highly - it's the only book that ever made me laugh out loud in public (on the subway in NYC). Read it!!