They do seem to be extremely close friends, if they're not an item they must have a really complicated relationship! I know its not any of our business what they do ... but .. interesting nevertheless.
On FA itself they didnt say much, but they're conversations on their radio show were fascinating. How sweet that she chose a song for Colin's birthday with a lyric about listening to a DJ on the radio, she must have planned that really carefully to leave that particular song until his actual birthday.
But then again I cant understand why if they are an item, they wouldnt admit it?