Pros:

Many compartments useful for holding a wide variety of stuff.  It has compartments suitable for pens, pencils, IDs, cell phones, iPods, a 20oz water bottle, a large pad of paper, a checkbook, and even a clear section that is great for stashing printed directions from Google Maps.  You name it, you can find a place for it.  Many of the places are also surprisingly well thought out.

Mine was cheap.  I think I spent $20 on it.

Mehs:

Heavy Canvas.  The bag is made from thick cotton duck canvas.  In many places it is double sided and encloses some sort of stiffener that might be plastic or cardboard.  This means that I really don't feel shy about tucking my netbook in the back pocket, because it feels sturdy and stiff.  Meh, because that weight is a double-edged sword.  All that heavy cotton duck canvas adds up.  This bag is also surprisingly heavy for it's size.

Cons:

Cheap construction.  I've owned the bag for less than 4 months and the clasp for the flap closure has already broken.  And it doesn't surprise me because it's a cheap metal stamping that is basically stapled in place.  But I thought it would at least last a year, not 4 months.  I'm still able to use the bag, but I'm already shopping for it's replacement.

I probably won't buy this bag again.  I wouldn't have bought it the first time for the $30+ dollars they seem to be going for now.  But for $20 shipped, it was worth the gamble.