As we all know by now, J.K. Rowling maintains an active presence on Twitter, and apparently keeps an eye on her old Harry Potter actors (see her priceless reaction to Matthew Lewis' shirtless photos back in May). Today, she gave her seal of approval to a series of friendly ribbings between Lewis (who played Neville Longbottom) and Tom Felton (who played Draco Malfoy).
Matthew Lewis who plays Neville Longbottom in the Harry Potter series thinks Alan's performance as Severus Snape in Deathly Hallows is the best performance of anyone in the entire series! You are so right, Matthew. :)