The eye tracking technology seems fascinating. It is very interesting that a computer by means of the language of glances could sense and interpret the eye motion data. This technology can have a huge influence on the field of the medical technology and can be helpful in the better interpretation of the mechanism of the vision as the article mentions.
Maybe by menacing imagery, Sutherland wanted to point out to the unimaginable powers or abilities this technology can give us or he wants to point out that the science and technology always can be used in different ways (bad or good).
Haptic technology is not listed in the article. Haptic technology is used to create the sense of the touch for controlling the objects in the virtual world. It is very useful in the medical technology for helping patients with chronic pains. It can be helpful in the better interpretation of how human sense of touch works.
The separation of the presence and the form make sense to me especially in the context of the form and content. Distinguishing presence from the immersion or form from the content helps to improve the vicarious feeling created in the virtual worlds.
I agree that present is possible in the impossible world. Considering presence as a response to a given level of immersion, then by improving the level of the immersion, the response will become stronger.
This video clip about Hpatic technology for Dental Trainers is interesting.
http://www.moog.com/markets/medical-dental-simulation/haptic-technology-in-the-moog-simodont-dental-trainer/
Also Slater’s blog seems interesting to me: http://presence-thoughts.blogspot.com/