Just watched Thursday night's "Fringe" episode, "Peter" I didn't have my mind blown like so many "Fringe" fanbois (and girls). But I think John Noble is the best part of "Fringe" so any episode focusing on him for an hour is fine by me. Though it didn't hit me in the "OH. MY. GAWD!" way it seemed to hit many people, it was a solid hour and definitely one of the more enjoyable episodes of "Fringe."
I enjoyed the notion of an alternate universe where Eric Stoltz starred in "Back to the Future" instead of Michael J. Fox. I wonder if Fox played the role of Rocky in "Mask" in that universe, or, for that matter Daniel Graystone on "Caprica."
My favorite part of the episode might have been the retro opening credits. Nothing is up on Hulu yet, and I can't embed it, but you can view a clip of the opening credits on Fox's site, and the entire episode is already up there as well.
Update: here's an embed of last night's opening (Thanks, Christopher):