Shades of Milk and Honey is billed as a sort of cross between Jane Austen and standard fantasy, and this sort of description is accurate enough in explaining its general format. Mary Robinette Kowal's writing in no way resembles Austen's (to use a word Kowal seems overly fond of, Austen's writing is a bit more "droll"), but the styling and personality match a lot of modern interpretations of Austen's style. Kowal uses little tricks to make the writing feel older ("shew", "surprize", etc.), and while they're clearly modernized and indeed the writing feels very, very contemporary at times, these small touches nonetheless create the sort of Austen-esque aura that Kowal was hoping for.
In truth, Shades of Milk and Honey reads much more like standard historical-fiction-romance than it does like Austen, but here the fantasy aspects come in and turn a fairly middling book into something much nicer. In Kowal's world, magic can be used to create various glamours, largely used by women in adding small touches to paintings, or music, or for small performances. Glamours may also be used to alter one's appearance (for a short time, since working glamour can make you ill), an interesting (if minor) point about appearances that Kowal underplays nicely. However, these glamours are also used for grander artistic effect, and much of the story revolves around one such glamourist and his relationship with our main character (a "plain Jane", no less).
Kowal does a lovely job of making her magic seem utterly real. It's viewed much like other artistic styles - something that needs to be learned, studied, and honed, but also relies on native talent. Throughout the book, Kowal explores different aspects of art through the glamour - performance art, visual art, and music as well - in a surprisingly in-depth way. It's not a brilliant meditation on the subject, but it provides depth to an otherwise largely straight-forward novel.
I liked Shades of Milk and Honey a lot, but I liked it in the same way that I like watching a lot of period dramas - it's meant more for the mood and styling than anything else. The story is extremely predictable and there were a few missed opportunities in the characterizations (particularly regarding Jane's younger sister Melody, who I wanted to see more of). And of course the writing is not really Austen-like, it's Austen-lite. There's a distinct lack of any social commentary, which I felt was another missed opportunity. Only one scene really touched on the matter, but it handled it quite well and I hope to see more care given to it in the sequels. Yes, I'll be reading the sequels - this was a wonderful way to spend an evening. The glamour adds the necessary touch to an otherwise standard romance, transforming it into a sweet and enjoyable historical-fantasy romp.