I have a Novara (REI) Randonee, which is a touring bike. It is a good comuter. You might also look over the Cyclo-Cross bikes. With only two chain rings, they might let you down on big hills, but I notice that that's what most bike messengers use, so they probably work out well in traffic. They are supposed to be nimble and quick shifting.
Somehow, I visualize you as having more of a greyhound build and less of the Clydesdale physique. You might even find yourself comfortable on a road bike, though I suspect either touring or cyclo-cross are probably better choices for that kind of distance. Whatever you get, get it at a bike shop, and be sure it can be fitted with fenders. Most road bikes don't have enough clearance around the tires. All touring bikes should either ship with fenders, or be able to accommodate them.
If your route has really rough pavement, you might need a mountain bike. Big, high volumn tires are the most important part of your suspension. Suspension front fork helps, too. Personally, I have never met a mountain with geometry I found comfortable.