Personally, I'm a fan of Kevin Smith and listen to his podcasts. Still, I was hesitant to read "The Widening Gyre", mainly due to Smith's admission that he wrote some of the comic under the influence. There's a difference between hosting a jokey podcast stoned, and crafting a massive Batman series stoned.
The book truly took me by surprise. Smith's writing is crisp, and his innuendo-heavy dialog rarely felt out of place (mostly because he writes Batman rather traditionally). He tells a tale that's a mix of the "Batman: Knightfall" arc (in its basic plot) and one of the best Bond movies. Telling you which one might spoil too much, though.
The book isn't perfect. Some of the flashbacks felt diversionary, though as a whole they do suggest that this Batman is a little too nostalgic and soft for his own good. Additionally, Flanagan's artwork is solid but not stunning. He's most comfortable drawing carnage and gore, but the more emotional scenes lacked punch. That said, I'd love to see his art improve in the second half of the arc.
Which brings us to my last, minor squibble. Without dishing out any spoilers, "Gyre" ends on a stunning note that makes the book a must-read for any fan of the Dark Knight. However, I haven't heard any news on when Smith intends to finish his story. I hope chronic lateness doesn't strike again, because that last page demands some follow-through.