Peter Jackson just confirmed on Facebook that Orlando Bloom will return as Legolas in The Hobbit films! This is what the filmmaker said:
Ten years ago, Orlando Bloom created an iconic character with his portrayal of Legolas. I'm excited to announce today that we'll be revisiting Middle Earth with him once more. I’m thrilled to be working with Orlando again. Funny thing is, I look older—and he doesn’t! I guess that's why he makes such a wonderful elf.