Brilliant, again. Wouldn't want to say it was either better or worse than A Wild Sheep Chase, but it's certainly more ambitious - Toru Okada is more transparently (so to speak) an 'everyman'-type character than the unnamed narrator of A Wild Sheep Chase and is also much more fully-realised, and his story is more explicitly a quest for meaning twinned with an examination of the nature of identity (I'm standing by my initial diagnosis of those two themes as the key ones in Murakami's writing). One really gets the sense that Murakami is grappling with these big questions - the text seems to be in some sense open to different answers, and different types of answers, and while the conclusion arrived at by the novel is important (insofar as it's a conclusion at all), it also feels at least potentially contingent and polysemous.
But it's not all big picture stuff - indeed, any such attempt would be, I think, inimical to Murakami's particular literary-philosophical method and convictions. In fact, much of the joy of The Wind-Up Bird Chronicle lies in the details: in the intricate, whimsical, detached-quixotic characters (not to mention writing - a telling parallel) and the odd things they do (especially our hero Toru Okada, and the fey, quirky May Kasahara); in the unassuming manners in which people drift into each others' lives and form connections which are meaningful whether tenuous or enduring, or both; in the blurring of the line between reality and otherness (dreams, fantasy, the unconscious); and, relatedly, in the metaphors-made-literal (or is that vice versa? or both?) like Toru's sojourns in the well, the double life of Kumiko, the figures like Cinnamon and Ushikawa who seem to have come straight from some kind of collective storybook of the unconscious, and of course the wind-up bird itself...I haven't been as excited about a newly-discovered writer as I am about Murakami in ages.