Chris Priestly wrote...
I've said this before, and I'll say it again: I hope we do not reveal her face.
Why not? Well, no matter what she looks like under there or how well a job the team does with the reveal, it will never live up to what I personally have in my own imagination. Don't get me wrong, I know if they choose to reveal her face, they will put a lot of time and effort into making it the moment fans have been waiting for. However, it just won't live up to what I have in my mind's eye.
Take, say, the Harry Potter films. I read the books before seeing the movies and even though I think the cast did an awesome job in the roles they were cast for, they weren't exactly what I had envisioned Dumbledore or house elves looking like, or Snape or dragons sounding like, etc. What was done was awesome work, but it was (for me) just a tiny bit wrong at the same time.
Before Tali's face is revealed there is huge speculation on what she looks like. Is she pretty or ugly, is she humanoid or more alien, nose or no nose, eye and skin color, etc. All the things fans have been guessing and speculating and fan arting for years now. Once we reveal her THAT is what Tali looks like. No more guessing or hoping or whatever. I know that if her face is revealed many people will be happy, but I know there will be those who are upset because we will have "got it wrong". We won't have gotten it wrong as we are the creators and what we say goes (yeah, I know how that sounds, but you get what I mean), but for those people we will have gotten it wrong as we won't have lived up to their vision of what she looks like.
So for me, I hope they don't reveal her face. I also get why people want to see it, but I prefer to leave it up to my imagination to determine her look. Still, I have no say in whether her face is shown or not. Casey and the team will weigh all the pros and cons and make the right choice and we'll all see whether they reveal it or not. Stay tuned. 

I'm sure I'm not the only one who has said so, but I think the perfect solution would be to allow the player to make the choice.
Go through the time and effort to create an "official" face, but only enable players who have romanced (and not cheated on) Tali to be able to see it. Even then, allow the player a choice regarding whether or not they want to see it. Granted, it'll be plastered all over the internet 0.00003 seconds after the game is released, but that doesn't meana a player *must* see Tali's face in-game.
Stephen King did a great job with this at the end of the Dark Tower series. He ended the storyline in the way he wanted, but he also understood that the audience might want to see more. He created more, but sealed the pages at the end of the book with a physical lock that required the reader to tear it. King warned that the additional pages were "canon," but that the reader might not want to know that part of the story. Naturally, almost everyone read them, but I'm sure there were some who didn't... wanting to preserve the story the way it was originally laid out.