Here are a few shots of the backpack itself
It's supposed to fit a 15' laptop I'm not sure how big the one in the picture is it's my parents I just grabbed it to take the picture. Also with the books I have in it there is still a decent amount of space left, easily room for at least 1 more big textbook.
This is just a shot of the front pocket area, honestly I almost never split the bag like it is in the picture I just reach down and grab what I need but the option is there I guess.
Just a shot of the back, it is padded and sectioned to form around your body when the straps are used. Also the pocket on top is the one that has the slit to pass headphone wires through. Instead I usually keep a camelbak bladder in there and pass the nozzle through the rings on the shoulder straps. The little cell phone pouch on the right strap in the picture (left when worn) probably wont hold larger pdas but something like an iphone should fit no problem, I have a pantech duo and it fits with ease.
Finally a shot with the backpack on, I'm about 6' and as you can see the pack takes up a decent portion of my back, when I ride I have it higher up on my shoulders but even the way it is in the picture it's still well above my butt.
The only downside really about this bag is that it's not as quick as something that just zippers since you have to unbuckle and flip the top every time to open and close it. It's something I've grown used to and really doesn't bother me, I'm never in that big a rush that half a minute would make a huge difference. I compare it to riding gear, yes it takes a bit longer to get ready but in the end it's time well spent. Another plus is that this backpack is very unique, at a school with 40,000 plus students I've never seen another one. As a matter of fact I've only seen this backpack one other time at some airport but I don't remember where.