The switch to a widescreen format is a fantastic and much overdue development and it serves the cinematic feel of the series well. The framing in this first episode seemed a bit "off" to me, as though it was simply matted to letterbox from a full screen source but I can't be sure.
Anyway, count me as one of those fans who do not like the use of voiceovers in this episode. They are, on the whole, rather badly written and more than a little pretentious sounding. They are also way, way overused in this episode, to the point that they kill the action onscreen. At one point, we have Mulder striding down a hallway in the secret DARPA complex while he gives us a voiceover explaining that he is, indeed, walking down the corridor. A deadly boring use of voiceover. Previous episodes in Season Four were able to use voiceover to great effect and so it's a mystery why Chris Carter stumbles so badly here.
One other criticism is that I found the acting a bit "wooden" in this episode, as though the actors had yet to shake away the cobwebs from their summer break. There's just the slightest loss of chemistry here that I hope is regained as the season progresses.