When I first saw Eureka's "Once in a Lifetime", I thought it was a joke to have Zoey be valedictorian in a future that will never happen. Then I realized that to be valedictorian, she had to smarter than a school full of geniuses. A subtle way to hint that Zoey is smarter than she gives herself credit for. A fact we latter learn to be true when she scores a 157 on her IQ test, but tells her dad it was 112.
Taking the Historical In-Joke to its logical conclusion, if the Einstein-Grant bridge became the Einstein-Rosen bridge after the timeline changed, then that means EVERYTHING prior to the Season 4 premiere occurs in an alternate universe to our own, and it is only now that history is put "right". It may never be significant, but it is an odd thought.
