First of all, all three platforms ran at a solid 60 frames-per-second without hitching even during intense action. Now, obviously, the PC version looked the best, but the differences aren't that major. Had the PC version not been running in between the two console versions, I would have been completely satisfied with the look of the console versions.
The biggest differences between the platforms--again, the game is a year out from release and still in development--are the load times. The PC version shot ahead of the consoles, while the Xbox 360 loaded next. The PS3 version lagged behind, but this could easily be chalked up to the ongoing development process and not be representative of the final product.
In the end, all three versions looked amazing and were smooth throughout. Those that require the absolute best fidelity will want the PC version, but gamers shouldn't feel like they are getting an inferior product on the console.
Rage will be released on September 13, 2011 in the US and two days later in Europe.