Merrick here...
It's easy to get lost in the bewildering maze of rumors regarding whether or not Arnold will appear in TERMINATOR SALVATION. And, until we get either an official denial...or see for ourselves...the following should be treated as educated speculation at best. The last I heard, a Schwarzenegger associate named Roland Kickinger had been hired to fill Arnold's T-800 role for a sequence in the film (HERE). This was back in mid-July. The report over at Latino Review now says this is correct...but only to a degree. One of LR's sources is telling them that Kickinger will, essentially, do the grunt work as the T-800 - but Arnold's face will be digitally mapped over Roland's, and dialogue snippets from Arnold will be incorporated via ADR. As supporting evidence, LR's source sent in a picture purporting to show the on-set meeting of Schwarzenegger and Christian Bale. You can read more, and find said image...

HERE!!!

This facial replacement technique has been in play for some time now. The first time I recall hearing about it was for the shot where the girl falls from the air duct (with the raptors snapping below) in JURASSIC PARK (i.e. stunt woman with the child's face dropped in). It may've been used before that, though. Not sure. So...rampant misinformation? Wishful thinking and nice Photoshopping? Or, have the pieces of the puzzle finally fallen into place? Discuss below...