What started as rumors has now come to pass, as young British actor Finn Jones has been cast in the role of Ser Loras Tyrell, the Knight of Flowers. A young, brash knight, younger son of a great lord of the realm, Ser Loras is famed for his youthful beauty and his prodigious skill on the tourney ground. GRRM adds some more details, noting that while the decisions had been made to cast him when rumors came out, the actual contracts and the like had not been signed until very recently. GRRM adds that the audition scene for Ser Loras was a scene from the third book, A Storm of Swords.
Embedded below is a reel of Finn Jones: