Mr. Juhlin has an updated guide of his huge (and hugely expensive) but outdated "4000 Champagnes" opus magnum, as it were. This is the book to take with you to Champagne or to your local shop. He knows his subject supremely.
He presents the makers alphabetically. He provides a blurb on each, followed by details of all their recent offerings, with his ratings. I have yet to differ with any to notable degree. I have had only about fifty or of his exhaustive listing (I find only one missing), but enough to give blind confidence to use as a purchasing guide to this pricey pastime. That is real value to me.
As a guide, it is all it should be. If you want more detail on only the latest, it would be a good idea to subscribe to Parker's letter. But I would take Juhlin with me on site. He is more of a specialist than Parker. I just wish he made this a cheaper annual without the otherwise pleasing, high quality paper binding and enjoyable photographs. Useful maps.
NB: If you are looking for sparkling wine, not made in Champagne proper, then go to Stevenson. And Parker is still a solid companion. But true Champagne has become more popular in the U.S., even though so many Champagne houses have a large California presence. We are now third in consumption behind the U.K. and the BBC.