So my Vive arrived today. Initial impressions on E : D usage coming up...
I am seeing a strange light streaking effect that looks to me like lens reflection, but is most likely a rendering issue. I haven't proven this yet, but I've also not seen the issue in any other games or demos.
Curiously, I'm not getting the text issues that others are seeing (it's
much better for me than on the DK2), I can read everything the game throws at me. I
am using a blue colour scheme, however (I do even when playing Elite on my monitor).
Framerate, surprisingly, has not dropped at all as far as I could tell, which it did occasionally (sometimes brutally) on the DK2 - it's been fine in all situations so far (including rings, gas giants, SC, normal space, etc.) but I've not gone down to planets yet so I may update this post when I do that. (FYI this is on a 980 Ti, using VR High settings).
Overall, light streaking thing notwithstanding, Elite looks fantastic on the Vive.
Also, just being able to turn fully around, and see the entire ship without the DK2's camera giving up on me is
wonderful 
(I'd like to be able to turn the wall grid off when you get out the chair though, since it shows all the time once you do that, not just when you approach the walls).
So, initial impressions are very positive indeed. Probably some tweaks to be done by Frontier, but looking good!
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UPDATE EDIT: Okay, so after some more game sessions, I have to amend this somewhat.
The streaky light effect gets more irritating as play goes on, especially in really dark spots where the UI streaks all across the screen.
I have now seen SC stuttering (and a bit at stations), just like I sometimes did on the DK2

This doesn't always happen and seems to vary between launches of the game in the same locations.
I've also noticed a bit of difficulty reading text at the fringes, though it still doesn't seem as severe as others have said (and I got this a bit on the DK2 too, so it might be my eyesight

)
Still, further play has diminished my initial positive reception somewhat. Hope these are issues Frontier knows about, and are working on, because otherwise the game does look truly fantastic on this headset!
UPDATE EDIT 2:
This article seems to imply that the light streaks are actually an artifact of the lenses. In which case... this issue is unlikely to be solved for Elite, without HTC producing lenses similar to the custom ones Oculus designed.
Can anyone who knows more about optics confirm / deny this?