I have mixed feelings about Russell Brand. On the downside, I thought his performance alongside Noel Fielding (who I do normally like) on The Big Fat Quiz of the Year was a bit embarrassing - too much like a pair of naughty schoolboys - his radio show gives me a headache, and of course I will forever associate him with THAT bl00dy programme (you know, the one with Davina McShouty and Dermot O'Dreary, and a load of chavs and other brain donors in a pretend house).
On the upside, I think he's a good chat show guest, particularly with Jonathan Ross, but his best medium IMHO is stand-up comedy. I saw some of his stand-up stuff on YouTube just out of curiosity and my opinion of him went up considerably.