We are on REI's Gear Mail email list. The current issue is on cycling: Rock the Bike Lane. If you you don't subscribe, it's worth taking a look. The videos on riding in traffic are very helpful.

REI's Gear Mail newsletter link to current issue:
http://www.rei.com/email/gearmail/gm042310_snow.html

Direct link to REI article (with videos) on Riding Your Bike in Traffic. Very useful tips & videos:
http://www.rei.com/expertadvice/articles/riding+traffic.html