Lipsync and Facial Expressions and The Uncanny Valley

I've talked about the Uncanny Valley before when it comes to avatars in a virtual world, and how close Second Life is to getting avatars to a convincing level and not be "freaky-looking".

The topic has come up again in the SL Developers mailing list in regards to a discussion on whether or not to make lip-sync a default setting in a newer version of the Second Life client. For those unaware, you can turn on facial lip-sync through your "Advanced" menu, and when you use voice chat with Second Life, you'll see avatars lips move as they talk. It's not perfect, but it's pretty good. So good, in fact, that a whole lot of the machinima I see produced with Second Life uses that feature to make it look better. And it's a built-in feature with some of the middle and higher end Logitech webcams.

Now, I've been beating the drums for facial expressions and lipsync on avatars for 3+ years now. And Mitch Kapor has sunk research into the same area. So you should know my thoughts on this, but I want to hear yours.

Have you used the lipsync feature in Second Life? Other virtual worlds and/or video games? Does it enhance your experience or detract? Does it make all/some avatars look more/less real? More/less freaky?

Have you not used it? Go try it. You'll need the Second Life Release Candidate, voice chat on, and the select Advanced (if you don't have an Advanced, hit control-shift-alt-D), then Character, then Lipsync (Beta).

Let's hear your feedback!