There's little that's new here - much of Lance Armstrong's 'antics' have been well documented and what this book does is put everything together into a relatively cohesive structure.
Sometimes the order seems a bit off, jumping back and forth in the other cyclist's chapters, for instance Floyd Landis, but it generally holds together well.
It's not as personal as David Walsh's book, which leaves it up to the reader/listener to decide if that's a good or bad thing. For me, at times, it felt as if Juliet was listing things that happened, as opposed to explaining how she was involved in asking certain questions. David Walsh's version perhaps veers too far the other way but each book has its own merits (though I suspect Walsh himself would be surprised to hear himself called an "English" journalist - he's most definitely Irish).
All in all, if you've decided to buy this, you likely already know what you're getting - a dossier chronicling Lance Armstrong's years of cheating. Everything publicly known is there and, for that, it does what it should do.