I started a label with my friend Bakir that is all dubstep with live instruments being performed on the tracks.
http://www.myspace.com/dubsalive
Bakir and I have performed together in a number of live formats, sometimes just laptops and trumpet. Other times Laptops, and myself switching between Guitar, Bass, Drums, and Bakir does Keys, Trumpet Melodica. While one is playing the other mixes in tunes on the laptop (and we defo go for a fast paced dj style of mixing and play dubs that are not edited to sections and are by lots of different dubstep people in addition to ourselves.)
That being said, I think live dubstep is a critical part of the genre and should continue to be supported and developed.
It's comical to me how some people on here are hating on rock drumming. Listen to Emalkays, "Mecha." Sounds like rock drumming influence to me. If you want drummers with pocket's who not only have the skills to lay down hard dubstep kicks and snares and are minimal enough to give you the dancefloor vibe, check out, Brain, Kenwood Dennard, KJ Sawka, the drummer from "Lake Trout" (yall will love these guys," Jo Jo Mayer, Eric Kerr (and these are just a very few).
I think band can certainly pull of a dj sounding dancefloor set with minimal use of live instruments and get people dancing hard. There is most certainly a powerful vibe when the audience member is in sync with the performers as they create the sound, VS a dj who has to audition tracks that they are going to mix in. At that point the dj doesn't experience what the audience is experiencing simultaneously. I do dj sets and live sets but I must say I often have more fun when there is no disconnect from me experiencing what the audience is experiencing versus the moments where I am listening to the next track I'm mixing in. I have had both styles of performance and variations there of get me off (as an audience member) equally as hard. Present good music the way you want to present it and get the the crowd excited by the music. Enough shooting the medium.
And let us not forget the mass appealing power of live instruments to the average music listener in the world. Live DnB bands like Reprazent and live performances like Squarepusher excited my JAZZ PROFESSORS at Berklee College of Music, to the point where those groups were taught to us in a number of different classes. So live bands, performances and instruments can also help get this genre to an even wider audience!
Oh yea and live projects at raves go OFF here in San Francisco. Some of the craziest underground electronic raves I have been to here in the city have featured live acts as the main performers.