I am not a member of either the pro- or anti- disc brake religions, which can get a bit fundamentalist and fanatical at times. But my tourer/commuter is one of the bikes that I really appreciate having disc brakes.
When I have the bike weighted down, when the weather is nasty, when I want to make a sudden stop - or moreso any combination of these - the discs really perform.
Commuting means I am usually carrying significant cargo weight, and liable to need an emergency stop whenever someone's car or dog or kid does something random (which is way too often). I've got Shimano 5800 hydraulic disc brake group on my touring/commuting bike and I would not trade it for anything. Awesome combination of durable, reliable, sweet-shifting, and fast stopping - and the cost is fairly reasonable for what you get. If I was thinking LHT, I'd get the frame and build it up with that group set and never look back.