If you don't know what performance practice is, I encourage you to Google it.
I've had a slight issue with this term since just before I went to college. The assumption that developing what's going on right now isn't as credible or important as preserving a 300 year old tradition is, in my opinion, crazy.
If for no other reason than job preservation, what will musicologists have to study in 2270?!
I like to use the term contemporary performance practice to begin to explain what it is that I do. To my mind, this covers how we perform the music being written today; the use of new interactive technologies, live surround sound or broadcast techniques, new performance tools and spaces, or simply how we notate and interpret contemporary scores...
I'm not suggesting we need to analyze every little note, gesture and squeak as we make and play them, but if we aren't creating culturally relevant work today, we could be the first creative generation to have nothing new and original to show for our efforts, and I for one think that would be a terrible shame.