i would say only switch if you are doing GRAPHIC DESIGN - PRINT MEDIA - PRINT ADVERTISING - FILM/MUSIC - OR ANYTHING ELSE as far as school goes... for the everyday user i would say just stay w/ Win its cheaper and it has everything you need, i currently have both but Win is by far the top OS b/c of availability, you can get anything you need and want for it.
Plus if you are switching over to mac i would wait b/c mac is having to design an OS to run on intel chips b/c IBM is no longer supplying them chips anymore, so you will see a mac running on PC platform very soon.