This article is worth reading, for those who wanna start the usual "mocap vs keyframe" animation debate.
Quite old but interesting nevertheless. Also great animator Michael Sporn commented on this issue back in January, with a lot of interesting points to clarify how motion capture can differ considerably from rotoscopy: http://www.michaelspornanimation.com/splog/?p=935
For me, as an animator who uses the classic principles of animation from Walt Disney on his works and adopts the classical style, I would say that Motion Capture could be good as a source of reference to work with, but I personally don't like it when the basis of the animated element consists of mocap data and then everything else is fleshed out "from it". This is clearly explained by Michael Sporn in his Splog:
The “animators” have become interchangeable and almost irrelevant.
You aren’t able to define anyone’s animation style behind any of Tom Hanks’ characters in Polar Express. You can only see Tom Hanks or Savion Glover in Happy Feet.
That's exactly what I mean. In Rotoscopy, you are able to appreciate the animators work because the drawings (or any way the animator would express himself) would showcase more the creativity of the artist than the live actors recorded performance. The creativity of the artist becomes the essence. But with characters like "DJ" from Monster House or "Santa Claus" from Polar Express the essence comes from the recorded live actors' acting and not the "drawings" of such characters in motion.
I do not think that Motion Capture is gonna kill keyframe animation and that is something "bad". Is just another "tool" that I'm barely familiar with and I've never had an interest in, seeing the results from other animation projects where it has been used. I admit I don't completely dislike it, and the main reason behind my openness towards it is the beautifully pulled off character of Gollum in the Lord Of The Rings movie Trilogy by Dir. Peter Jackson. I've never quite understood how Weta Digital really gave life to Gollum: some say it was purely Andy Serkis's performance that drove the character; others say that motion capture was used as the basis to flesh out keyframed animation from; and a few out there, the ones I would like to agree with the most, mentioned how mocap data was recorded "just as reference" and that talented animators created content from scratch. This would consequently support Sporn' views towards motion capture not being able "to help give the character a soul".
VFXWorld.com talks about "keyframe animators mimicking Andy Serkis’ movements" (http://vfxworld.com/?sa=adv&code=1e242f07&atype=articles&id=1974&page=2). I'm dying to know what do they mean by "mimicking" and "rotomation". I might be talking to the void here but if anyone out there could clarify this for me I would be very grateful!!