I was asked personally to share my thoughts on virtual instruments so here goes:
Virtual instruments and sampling are essential, in my opinion. When computers became powerful enough to run something like ProTools, the entire music industry changed. For the better? For the worse? That's open for interpretation. It definitely changed for the cheaper, though. With studio time and instrument prices being as expensive as they are, why not just download the synthesizer you want, or samples of any instrument for free, legally or otherwise, and save space, money, and time practicing? Now anyone can make music for free, which I think is fantastic. Of course, you have to take the Crystal Castles with the Ronald Jenkees, but you had good and bad music in any century.