You do know who Chris Evans is, right? The guy who made his name in irreverant light entertainment, and then brought new life to the Radio 2 Breakfast Show which is now more successful than it's ever been?
He's done everything from DFYT and TGI for the young 'uns, right up to proving himself a worthy successor to Terry Wogan and keeping the older generation happy. If he cannot do it, then it cannot be done.
Also, he knobbed Rose from Dr Who, which automatically makes him a bit of a legend.
i do just i think it will swing so far to the anorak enthusiast end of the scale your average family wont be entertained, numbers will drop and then the show