They should just take those two current dorks they're using in the "I'm a Mac...I'm a PC" spots and put THEM in different situations and scenarios. The PC guy could be on a big screen, droning on about pie charts. The little Keanu Jr. could put his bong down, don his favorite hoodie, come running in, throw something, etc.
The face of Apple, as it were.
Uhh...wait a minute.
