I reckon that this one takes 40 or so pages to properly hit its stride, which it does more or less from the point when the narrative settles down in Wellington, the New England university town where the Belseys - and, soon, the Kippses - make their home. In its setting, then, not to mention its frequently arch tone and the unsparing but rather sympathetic view it takes of its characters, On Beauty naturally brings Alison Lurie to mind for me, but the tone is more contemporary and more overtly concerned with Big Ideas and fashionable -isms (well, the title's a bit of a giveaway, huh?), and Smith - as we would expect from her - also pays much more attention to questions of identity, belonging, race, and family...one of the great strengths of the novel is the way in which it synthesises Smith's more abstract, philosophical concerns with these more down to earth, immediately relevant threads while wrapping the whole up in a Story, with Characters who exasperate us but force us to care about them, or at least respond to them as something more than purely symbolic figures (in a way which never happened in The Autograph Man).
If I were to attempt to leave all the comparisons (to Lurie, to Smith's previous novels, to everything else I've ever read, etc) aside for just one moment, I would simply say that I enjoyed On Beauty - it's easy to read yet also quite substantial, and the prose is deft without being intrusive (barring the occasional over-written descriptive passage which threw me out of the pure sensuous experience of reading and made me become aware that I was holding something constructed in my hands). But I'm also nagged by the elusive feeling that it's not quite all that, and I can't quite put my finger on the reason for the feeling.
Part of it, I think, is that, while I like her heaps, I also tend to be particularly critical of our Zadie. There are probably a few reasons for this: first, there's a sense in which I feel as if I've grown up with her, and as if I've watched her grow up as a writer (a continuing process on both ends, natch); second, and relatedly, she's a contemporary writer, writing about contemporary times; and third, and relatedly again, the milieus [pl?] about which she writes aren't all that far removed from my own (all things being relative)...so that might go some way to explaining why I liked On Beauty so much and yet don't feel completely sold on it.
I do think that Smith has a knack for characterisation - the Belseys and the Kippses all come to life, as do most of the minor characters, often with not a lot of 'page time'...they all seem to live and breathe, and I had the sense that I could begin to guess where they were coming from based on the few small interactions that I had with them - much like meeting people in real life! They're all impressively multi-faceted while always seeming to retain a basic integrity which makes them believable, and it was easy to visualise them, all of which is a testament to the author's skill. (I was, however, left a bit cold by the depictions of Carl and Monty - the former because he seemed a bit of a stock type, and not particularly interesting, and the latter because we always seem to be seeing him through others' eyes and we're given no real explanation for the affair with Chantelle (unless we're supposed to infer that, hey, he and Howard aren't so very different after all).
It's also interesting that, at least after a first read, Smith doesn't seem to have taken any particular stance on a lot of the issues which she raises in the novel. Howard Belsey and Monty Kipps are pretty clearly positioned on opposite sides of the ongoing 'culture wars', and we're given plenty of opportunities to see each of them in action and to observe the effects of their politics on their lives as well as their individual blind spots, but neither seems really to be endorsed. (Incidentally, I was initially a bit ambivalent about the writerly tactic of producing a book on beauty and then having one of the central protagonists be an academic/intellectual champion of anti-representational art (ie, he doesn't like the tomato), as opposed to, say, the more traditionally aesthetic responses of Kiki, but I'm willing to give her that one.) Similarly, there isn't - thank goodness - a clear line on just what 'beauty' is, which in fact (I think, though am not entirely sure) makes On Beauty a better novel.
I do want to go back and re-read White Teeth again some time - I'm with everyone I've spoken to about On Beauty in considering it a definite improvement from The Autograph Man, but I'd also like to go back and compare it to the one with which it all started...I suspect that this latest will turn out to be more mature, and quite possibly the better novel, but less joyfully full of the love of life and words...