Most people aren't wine geeks. Most people shouldn't be: That way lies madness.
But even casual wine enthusiasts enjoy learning a bit about the bottle they're drinking. For the bulk of the wine-loving population, Karen MacNeil's The Wine Bible is a good book, despite being out of date and not always as thorough as one might want. It gives casual wine enthusiasts solid answers to most of the questions they might ask.
For the nerds among us, there is The Oxford Companion to Wine, recently gussied up with a new edition. Wine writer extraordinaire Jancis Robinson edits the exhaustive and monstrous volume, which includes contributions from specialized experts: David Schildknecht, probably the English-speaking world's foremost authority on German and Austrian wine; Kym Anderson, Lead Economist of the World Bank's Development Research Group; and a host of Masters of Wine and other entrenched grape gurus (including Tyler Colman of Dr. Vino).
I wouldn't normally think the book needs a review; it's the ultimate resource for the vinous expert in the household. But I've been using it quite a bit in recent weeks, boning up on arcane bits of data I might need for my class, and I'm struck anew by its depth of information. Some of my books could tell me the name of the red-tinted soil under the vineyards in the Rheinterrasse portion of Germany's Rheinhessen region (Permian red shale) but few could also tell me Hungary's name for Grüner Veltliner (Zöldveltelini).
Like any good reference book, this encyclopedia's cross-references—paper hyperlinks, if you will—can take you on a journey of exploration that will last as long as your eyes stay glued to the book. Oddball grape varieties, every trellising system known to wine growers, and of course larger portraits of regions and general subjects fill the 800+ pages. As I've surfed the tome, I've learned new things about the regions I thought I knew so well. If you ever have a wine question that other books can't answer, take a look at this book the next time you're at your local independent bookstore. If you use the old edition with any frequency, it's probably worth shelling out the $65 to upgrade. The new volume has current information and discusses recent discoveries in wine science.
This book was sent to me as a review copy.