I think what he was getting at, when said consoles are better, is that the consoles only need half the processing power that a pc needs to run a game efficiently. Obviously a console doesnt need to take up system resources to run an OS..usually which require alot of mem to do so. Also, on a pc when running a game...there are still operations running and draining mem and cpu power, therefore, even a 2ghz cpu with 512mb ram and a 128 graphics card could have problems running a high end game. On a console, you could have a 300mzh cpu and less ram...and it'll do the job.
Where the consoles lose out however, is resolution wise, it can't live with the pc. Also the graphics solution is not upgradable. An x-box runs a revampt geforce 3 ti card. Which compared to an FX or Radeon, is nothin. Therefore you end up with less textures, poorer (note, i said poorer and not poor) anti aliasing and generally less detail.
So there is no simple answer to which is better, if you want pickup and play, multiplayer, less hassle/bugs then a console is better for gaming. If you dont mind putting up with bugs, upgrading hardware, and the hassle of installing, better graphics etc, then cpu is a better platform.