I just read the following on Bookreporter.com! I'm very excited, as I loved Hosseini's previous novels.
...it was reported that Khaled Hosseini’s new novel, And the Mountains Echoed, will release on May 21st from Riverhead Books. According to Hosseini, "My earlier novels [The Kite Runner and A Thousand Splendid Suns] were at heart tales of fatherhood and motherhood. My new novel is a multi-generational family story as well, this time revolving around brothers and sisters, and the ways in which they love, wound, betray, honor, and sacrifice for each other. I am thrilled at the chance to share this book with my readers."Yay!!