http://www.youtube.com/v/Xp-EVOPBhIo&hl=en&fs=1
Here's a cool video about turbo's by Holset.
Supercharger
Pros:
Power on demand.
Con:
Less potential for top end power
Turbo
Pros:
More efficient
More potential for top end power
Cons:
The turbo lag (especially on huge ginormous turbos)
More potential for failure