Thank God that's over. I might be alone in thinking 21st century studio Wilco (2002's overpraised "Yankee Hotel Foxtrot" and 2004's "A Ghost Is Born") to have thus far been indulgent and abstract, but it's left me pining for the twangy, truthful rock of the band's first three recordings. Now, with "Sky Blue Sky," Jeff Tweedy and the revolving door that is Wilco are back in alt-country. It's not the rootsy Americana of yore, however, but a satisfying throwback to golden ‘70s guitar rock, with deceptively subtle tunes gilding Tweedy's mellow lyrics about embracing ambiguity ("Maybe you still love me, maybe you don't") and accepting loss. Alas, a couple songs (like the noodly "Shake It Off') sound as though someone reanimated Jerry Garcia, but "Hate It Here" evokes Don Henley fronting "Sticky Fingers"-era Stones before stomping into a Wings-ish chorus, while the swooning outro of "Impossible Germany" channels Thin Lizzy's dueling guitar harmonies through a lush Southern drawl. Charmed, I'm sure. Again.