Steven1621 said:
what exactly are the advantages of the sleeve over a bag? i have heard about these sleeves, but i have never seen one.
Sorry for the delay in replying. The sleeve will fit your laptop like a skin. It has a scratch-resistant interior and durable nylon exterior. There is a little clip that holds your system in place, and two handles. I must point out though that the sleeve does not completely cover your PB. About an inch will be exposed along one side but I have never had any problems with my TiBook because of this.
I would recommend any sleeve regardless of what bag you go with. You don't want to throw your PB in with everything else. That is how sh-- happens. Also, if you were to drop your bag (and stranger things have happened) the sleeve should provide some impact-protection for the corners of the PB.
When I bought my sleeves (PB/iBook) for my girlfriend and I, I was planning to purchase a commuter bag down the road. However, I found that my regular North Face daypack does the trick just fine. But that is your call.
On a side note, you might want to also pick up a Marware keyboard protector (around $10) because with the lid on your PB closed, you may get key imprints on your LCD - especially if you have a book or 2 in your bag.