Everything will still work the same as always for the time being. But expect a lot of positive changes after he takes over including:
Automatic (and free) funding from Euro accounts.
Automatic ACH deposit and withdrawal.
Margin trading.
Interface redesign.
Lifting the $1000 a day withdrawal limit.
I'll leave you to decide how Mtgox is doing.
I'm guessing this was from Jed?
Well, MTG was a US only exchange then I believe. The interface has been redesigned and the $1000 limit can be lifted by verification. No margin trading. No automatic ACH but Dwolla has essentially taken charge of that. Furthermore it hasn't even been a year.
I think they're doing pretty good.