I'd rather use Opera on the Wii. The Wii has keyboard support, and you don't really need a mouse, the Wiimote works just fine. An old roommate had a PS3, I tried the Web Browser, and thought it was hideous. Just one more thing about that console that turned me off. I was planning on buying all 3 consoles until I played with my roommates PS3. Now I have no intentions of ever getting a PS3... I'm plenty happy with my 360 and Wii.
the ps3 browser Supports Far Far more online content. the Virtual keyboard is a pop up instead of the whole screen, and is better as a whole if you use mouse and keyboard. without mouse and keyboard its shit. but with it its basically using a PC