+2 about being courteous. Also be predictable and behave like a vehicle. ESPECIALLY at stop signs, lights, and intersections.

I've been bike commuting for about 4 years now; about 1/2 my commute is on a bike trail and the rest is on local roads. I also participate in large weeknight group rides sponsored by a local club. Frankly, I've seen far more traffic issues with the pack of riders forgetting they're on public roads and not in a race than I've had in total commuting.

My biggest gripe (and it is an issue for the drivers, not for me) is too many drivers do not know where the right side of their vehicle extends and think adequate clearance means most/all of the lane - so they put themselves at danger by going way over the yellow line to pass me - usually unnecessary for both of us to be safe. Surprisingly, I've found most drivers, even here in the self-absorbed Virginia suburbs of DC, to not get bent out of shape or put me at risk because I'm sharing the same road with them.

That doesn't rule out a few yahoos who think they own the road (and have no idea how much property and other taxes I may or may not be paying towards the same piece of asphalt), but I've yet to have any serious issues with them. Frankly, the most dangerous part of my commute are some of the other users of the bike trail (primarily dog walkers at oh-dark-thirty!).

It's worthwhile. Besides the non-trivial savings in gas and car costs, I get in exercise without taking excessive time from work or family, I'm in a better mood when I get to work and when I get home, I have NO problems finding a parking space close to my building or worrying about a parking lot dings, and I give my coworkers something to chat about (and found a few other cyclist buddies at the office).

Go for it, and tell your wife not to worry.