I tend to be against adapting books into movies, because you generally don't have time to be at all faithful to a book in such a short running time (the first couple of Harry Potter films were quite long because they wanted to hit so many plot points, but they still cut out all the character development). The popular Canadian miniseries from the '80s was a perfect example of this. It got a sense of the story across, but only just.
This is different. Fifty episodes are enough to do justice to a 38-chapter book. There's only one incident of any note that was cut, and several that were much fleshed out or added (plus one or two dull episodes that were mostly clips of earlier shows). You can be assured the creators really understand the characters and interpersonal dynamics of the story.
But is the story worth your while. You bet! A lot of folks link this series with Miyazaki, though he only worked on the first 15 episodes. More important were fellow Ghiblies Takahata and Kondo. But it FEELS like Miyazaki: strong, young, imaginative female lead steeped in the magic of Nature, learning to be loved by a grouchy but kindhearted elderly couple. All it needs is some flying machines!
It is worth digging on eBay for the possibly semi-legal region-free English subtitled DVDs. Don't mistake it for the recent Canadian animated series (which boggles the mind--surely it would've been cheaper to license and dub Akage no An!). This is, and surely always will be, the definitive film version of Anne of Green Gables. (You even get used to the "Konichiwa, Diana!")
