But there's also the arguement that Oro only said that because he puts so much faith in jutsus, and Itachi's Sharingan assures him of lots of jutsus, so therefore Oro assume's Itachi is stronger.

Don't get me wrong though, I myself believe that Itachi is the strongest character introduced so far (that is still currently alive). And I'm not a fanboy. I think if it came to the crunch, in a battle between the two of them Itachi would win.

But let's not get into that now, coz there's a whole allocated thread to that issue.