I managed to hack your last paragraph into 140 characters, in case anyone else wants to tweet it and look smart like I did. "Ebert judged films by their ambiti

I managed to hack your last paragraph into 140 characters, in case anyone else wants to tweet it and look smart like I did. "Ebert judged films by their ambitions, eschewing the ivory tower: action films needed but good action while cerebral ones had a higher bar." (Minus the quotation marks, that's 139 characters.)