That would sound about right to me.
I think it will go the same as Radio 1 did when Chris Moyles left. A lot of the due hard fans will refuse to tune in, then more will switch off as it will be really different to what they know.
However, as time goes by the numbers will stabilise and start...
Really weird one isn't it? I hope that he is good, I am just worried that we all have perceptions of him as Joey rather than a presenter!
It would have been great to get a few unknowns in that we could get to know and see their style grow