Recently, I started an online family tree on a site called Genoom I'm really enjoying the experience and I wanted to share the site's capabilities with others.
It's a great way to share photos, videos, stories, recipes etc.. with the entire family. And it's amazing to see just how many people we're related to. What I really like about the site is the ability to invite other family members who can also contribute and build on the tree. Everybody in the family can get involved. You can also have it to send you birthday reminders...very useful!
You can view an overview here: http://www.genoom.com/flash/en/whatisgenoom.html
or just get started at http://www.genoom.com
One tip for US users: Because it's based in Spain the dates are displayed dd/mm/year by default. You can change the date display in the user settings.