Increasing power drastically (S/C gives more like a 50% increase btw) will definately increase the wear rate of the engine. However, there are far too many other factors involved to say "it will decrease your engine's life by XX%. I have seen supercharged Mustangs go nearly 100K miles w/ hardly a problem, but I have also seen them blow up after 5k miles.
The bigest factor really is how the engine is used. ie there is a reason race engines are rebuilt far, far more often than your average toyota camry or ford taurus.
