Well another great question Shel......and so much to discuss about it as well...and lots of great points already made in here.
So, how do you do that? I guess it all comes down to how you look at it......to me, shooting a video is indeed about performing, because people are going to watch it. So when I record a video, I indeed feel, that you're all there and I act as such..
And as a viewer, I very much agree with everything Suzi said....I want a performer to engage with his audience, in any way possible. Years ago I went to see The Eagles, and also CSN, and gosh, both of them were boring as hell :S

....I'm sorry (I'm a major fan of both bands, you know that)....on the other hand, years ago I also went to Gloria Estefan's concert, and that was the biggest party you could ever imagine :woohoo: , best live-concert that I have ever attended! However, back to the original question, on camera it ain't much different. I for instance like it when a vocalist or musician smiles or looks in the camera. Not áll the time, but here and there. As a viewer you want to be engaged to the performer, to be a part of what he or she is doing, that he or she actually treats you asif you're there.
Actually our very own TG-master Neil is a very good example (at least to me),teachingwise that is, the way he communicates with the camera (read: US!), that's really hím! I honestly believe that he would talk to me exactly the same way in real life. And I think that makes him so appealing, he talks asif we're all there....wich we are, just not at thát particular moment. I think he does fantástic when it comes to that.
So when I started recording videos, the first ones, I thought they were terrible :S ! Gosh, I looked so damn serious, really not so great to watch. And in the beginning it feels strange to smile at a camera, but when I watched it back, I liked watching it much better. And ever since, i indeed really feel that you're all there, wich you all are, only not at that exact same moment, still I feel that you are, because you will be later..
However, you actually already named all the really important things that you have noticed, those are all very significant aspects of a true performer, I couldn't agree more. So yes, the playing is of course an important one (well it can make a difference at least, but it could be secundary for me too, as Suzi pointed out), for that I very much agree with Daryl...musical expression....I'm personally véry much into dynamics and more dynamics and yeah sustain sustain sustain

(dón't cut off bassnotes, go to other chords not too fast and not too late, let notes ring, don't kill them) But indeed, mute or deaden when needed. Playing soft, playing expressive, don't always play áll the strings of the chord you're holding, accents on the beats, vice versa, crescendo, descrendo. and for that you really got to FEEL the music (and/or know the original very well)..
So for example (sorry, more rambles, you asked!), this U2 video. Obviously the first one is a ballad, starts out softly...then after the first chorus another guitar comes in really strong and dissapears again when the second verse starts and the playing becomes softly again. Then the music swells and heads louder into the second chorus and......well then I got into the next song, wich has strong accents on the second and fourth beat (that's when a drummer plays his snare), so for that I muted the strings to kinda accentuate that. Then the third song, softer of course, a tad slower, so gradually applied that, otherwise the transition would have been too sudden or too abrupt, at least I felt so in this particular case....blah blah, and so on. Summary, I indeed pay attention to details in my playing, no matter if it's an 'easy'song or not, but because I can feel the music, it makes me not needing to think about it.....
Well in order to get all of that down without thinking too much, I guess it comes down to real passion, at least that goes for me. Passion for music, passion for playing, passion for people, wich makes me wanna share it and make people happy and share the joy i'm feeling when playing...and yes you gotta be yourself and sincerely mean everything you're doing, otherwise it won't work, before you know it, you're overdoing it..
....and really share yóurself is actually quite vulnerable here and there....
Oooooooh I feel I'm not done at all :S.....besides playing, I so lóve to talk about music and so on, I can talk about it for ages and ages, haha! :silly:
Ness