I found concert photography to be very exciting, both content wise and technically. Depending on your access to the stage, you generally have very limited angles and backgrounds to frame your picture. Of course the varied lighting also means you have nearly countless possibilities from that same vantage point.
During a concert, the energy makes for a very fast paced environment where your shooting constantly just to keep up with the lighting changes. Speaking lighting, as soon as your settings are perfect for a low key back light, the lighting program changes and now you have too much light. As soon as that happens and you adjust the camera settings, it changes again. Its these changes that make it challenging as well as exciting.
If your lucky enough to have clearance to back stage as well as front of house, you are sure to have the opportunity to not only capture some great images, but also tell a great story of the technical aspects of the sound engineering as well as the band's interaction with the crowd.