Aside from being pure Art Bell stuff (soldier from the future comes back to warn Earth of impending disaster, etc), this "John Titor" story is also nothing more than an elaborate hoax.
All you have to do to prove this is take a few minutes to check out the "evidence photos" that go along with it.
Specifically, look closely at this one :
The promoters of this story claim that this photo shows a hand-held laser being "bent" by the gravitational field of Mr. Titor's (alleged) "time machine". Impressed? You shouldn't be. Look closer.
The image is phony.
If this did, indeed, show light being "bent" in the presence of a gravitational field, then *all* light passing through that field should be "bent" -- including the light from the scenery *behind* the laser. IOW, if this image actually showed what it claims to show, then the scenery behind the laser should appear distorted (due to its light being "bent" on its way to the camera). However, no such distortion is visible. Thus, no actual "gravitational field" exists in this picture, and image of the "bent laser" is fake.
Since this "bent laser" image is provably a fake (see above), we know that it must therefore have been added to the picture after-the-fact. From the looks of it, it's probably a real image of a "laser passing through smoke", which was then digitally "bent" using PhotoShop or a similar photo-editor and, finally, pasted into the original to make it look like it was coming from the laser-pointer the man is holding.
Verdict: aggressive hoax.
MDN