It's viable, but I think over all it's a little bit less convenient when you have to mess around with the bike, lights, helmet, etc. My place is about a 3 minute walk from the station so it's basically just step out the door and on to the train and then I'm there.
I don't mind riding my bike around to the nearby shops on the weekend but usually its just most convenient to get places on foot or by PT. I only really do it for fun and fitness rather than it being the fastest way to get around.