I'm about a third of the way through now (not a lot of reading time at the moment). Your characters are rich, your worldbuilding is breathtaking, and the layers of conspiracy you're juggling are brilliant. This is a wonderful story.
ADDED MUCH LATER: Here's my review, posted on both Amazon.com and B&N.com:
5 Stars
A Brilliant Debut Novel
In a breathtaking Elizabethan England that never was, magic, conspiracy, swordsmen, playwrights and actors collide as an ambassador for the vaguely elvish skraylings is asked to select a winner from several plays written in honor of his arrival.
Maliverny Catlyn, swordsman with an unnerving past connection to the skraylings, is chosen to be the ambassador's guard---and finds his old friendships with London actors a sudden source of danger, intrigue, and near-death experiences as he stands between serving the Queen, protecting the ambassador, and trying to uncover the truth about various factions out to kill his charge. Or him. Or his twin brother.
The characters are all richly drawn, the history---including Lyle's use of real history and her revisions for this alternate universe---is wonderfully presented, the worldbuilding is incredible, London is simply amazing and feels touchably real, and the story is FUN. Fun to read, fun to puzzle out, fun to fall in love with.
This is the first book of a series, but Lyle's done a wonderful job of both making it stand on its own, and of adding a teaser at the end that has me waiting eagerly for the next book.
And here I need to add a quick disclaimer: Anne Lyle is a student of several of my writing course, but I did not see or assist with any of her work while the book was in progress, nor did I receive a review request or free book from either her or her publisher. I bought my copy, read the book, and was thrilled by how wonderful it was.
I read a lot, across genres, and in many areas of fiction and nonfiction This is the best fantasy novel I've read in the last few years.