I <3 my kegs.
Advantages of kegging:
1) Saves you about an hour (or more) per 5gal batch. If you do a batch a week, that's six and a half workdays of time per year you could be doing something else
2) A 5gal corny keg takes up a lot less horizontal space than two and a half cases of bottled beer
3) You aren't using up bottlecaps! Kegs are entirely reusable, so you're going green!
4) Women will love you, men will want to be you, and animals will want to learn how to talk so they can hang out with you! Having beer on tap is manly and increases testosterone production
5) You can always bottle if you keg, but you can't keg unless you . . keg
(hmmm)
6) Kegs are easier to carry and transport, and if you get in a car crash with a keg you aren't stuck hanging upside-down from your seatbelt in the overturned car while covered in beer and glass shards, waiting for Fireman Joe to show up with the Jaws of Life (although you may end up with a hell of a mouse over your eye from the keg if you don't buckle her up in the safety straps)
7) If you make your woman angry it's awfully hard for her to smash a keg on the coffee table and brandish it at you as she chases you down the block