This is one of my most used and favorite app on my iPhone. VideoUp allows video to be uploaded directly to Facebook. It works awesome and I have used it a ton. I have shot videos just about everywhere and then uploaded them to share on my Facebook page. It is not the same as streaming video, but it works great. Ustream Broadcaster offers streaming capability through their new app for the iPhone that works with the iPhone 3G as well.
Check this app out if you like to shoot videos and then share them on Facebook. If live streaming from your iPhone is your thing, then try Ustream’s new app.