Little known Aaron Williamson is a career bodybuilder, whom has worked in the movie industry thus far as a fitness trainer, such as on last years G.I. Joe: Retaliation (pictured below left with star Dwayne "The Rock" Johnson). But now it seems he has landed a starring role in Alan Taylor's reboot/sequel Terminator Genesis, and as a T-800 nonetheless, according to a post on the Terminator Fans site, that has since been deleted, which is reported to have said...
“Thanks to an amazing team of people who help me get better each week, both physically & creatively, I’ll be playing a T-800 (Terminator) in the upcoming production ‘Terminator: Genesis’. I’m extremely grateful & motivated as this new chapter begins to take shape.”
From the above statement many have speculated that Aaron will be playing a younger version of Arnold, possibly with the use of CGI. Though a highly viable possibility; as this technique was used in Terminator Salvation with body double Roland Kickinger, there is of course another, more likely possibility...
In 1984's The Terminator, Arnold Schwarzenegger was not the only member of the movies cast to play a T-800 Terminator; Bodybuilder Franco Columbo played a T-800 Terminator in the movies second future war dream sequences (as pictured below).
This is made possible by the fact that Arnold Schwarzenggers likeness belongs to the 101 Model of the Cyberdyne Systems Series 800 Infiltrator Terminator. Columbo's Series 800 was simply a different number model to Arnolds 101. Thus it is possible that Aaron could be playing yet another model number of the series 800.