It'd be SO easy to fake even ridiculously complex performances, as by design you can offload a lot of the skill onto the computer inside your guitar!
But, then again I suppose this is the same problem we have always had, and always will have- computers vs. art and creativity.
This is a false dilemma; computers and technology enable true producers and artists to do more amazing things. The poseurs will get wrapped up the technology and try to use it to paper over their lack of creativity, but the real artists will find a way to harness it. Look at Pixar.
The number of options you have is overwhelming. On a certain level I appreciate the number of options I'm afforded. On the other hand I feel like 'tweaking this' and 'changing that' takes a front seat, and the actual production of something worthwhile gets left behind.
Take a look at all of the overproduced albums you hear these days. It's not digital music's fault-- but it's a common problem.
Given the number of full playback performances that are already happening, I don't suppose the faking could get any worse. "Real" musicians will never fake a performance others in the industry will use all means available to them to fake their way to fame and fortune. Both ends of this spectrum are targeting different audiences though.