I think he will surprise - he isn't like the other riders we have had come through in the last few years - more a Stoner-esque rookie, but with the good gear.
As we have seen, talented riders like Lorenzo and Pedrosa are right up the front, on the right gear, but I put Marquez a level above them in talent - he blitzes the field and there are some similarly-talented riders to Lorenzo and Pedrosa circulating in Moto2 that he made look amateur.
Of the current 'new boys', I like Bradl, but he's a journeyman GP rider in my opinion, he will work hard to get better but doesn't have the brilliance Marquez has shown - his Moto2 championship was a bit of a gimme - do you think he would have won it if Marquez hadn't had his head-injury? Smith? Nah. Again, a journeyman that will work hard for his team and sponsors, but is missing that killer instinct. Crutchlow, Dovi? Two fighters, but without the right factory kit won't make a dent at the front. Aoyama, Barbera, Petrucci, Hernandez, Espargaro, Corti, all talented riders, but nothing to set the world on fire. Spies and Hayden - on the wrong bikes to do anything interesting (unless Ducati pulls a rabbit out of the hat)
Only Bautista and Ianonne seem to have the balls and talent and disregard for their own safety to fight for a position, assuming they had a ride capable. And Bautista has been notoriously gun-shy since he came to GP and busted his leg... still waiting to see some of the fire he showed in 250s against Simoncelli.
So really, who else is there to stop Marquez, apart from his team-mate, Lorenzo and a hopefully-resurgent Rossi?
If Marquez decides to fight it out, the other two Spaniards will get all upset at his lack of respect, only Rossi will take a blood-oath to smack the little ..... down, and he's capable - look how he disrupted Stoner who was on a clearly superior machine.
But I think if he learns his bike as quick as he has in the past, he will shock a few names with his ability to stick a wheel where it has no right to be and his raw talent and verve will show up Pedrosa and Lorenzo for the within-the-limits, safe bets they are.
It seems to me that, like Stoner, Marquez isn't prepared to accept second place if it's at all in his power to avoid it. He hates anything less than a clear track ahead - he sees another rider in front as an affront.
I'm prepared to make him my new infatuation.