I got new shoes last week and yesterday I snagged a timbuk2 medium sized bag for a good price. It's the custom color I wanted too, orange/yellow/orange. My old crumpler was a laptop bag and had way too much padding, plus it was black and I wanted them to see me from a mile away. The only thing I don't like is the timbuk2 cause of the design, is just a pile of fabric, there's no shape to it and it tends to sag and collapse, the crumpler kept its shape a lot better and the shoulder strap was wider, padded, and more comfortable.
The medium just fits everything I bring with me to work on a normal day, the large would've been nice but on the days I don't use it, it'll be like I'm carrying a windfoil on my back.