Robin McKinley's The Blue Sword is my all-time favorite book. It's got everything -- fantasy, a strong heroine, romance, and even a wry diplomacy.
I haven't been able to read her entire book list, but I was able to read her recent books Pegasus and Chalice. Reading them is like catching up with old friends.
I found Pegasus to be utterly absorbing - so much that I simply couldn't put it down until I had finished it. Pegasus is a story of humans and pegasi who coexist yet cannot communicate directly with each other. The bonding of twelve-year-old Princess Sylviianel and the fourteen-year-old pegasus Ebon changes all this. Aside from The Blue Sword, Pegasus is the McKinley book that I've found the most compelling since The Hero and The Crown and Deerskin.
Chalice is a shorter and to my mind, less interesting read. It's still worth reading however, to see how Chalice, the new Master and the Grand Seneschal hold Willowlands together.
Pegasus II comes out in 2012. I can hardly wait to read it.