"If you take handheld videos (on your smartphone, for example), the videos may suffer from shakiness. YouTube has an easy fix for this issue with their video stabilization editing feature."
Lifehacker has posted a nice tip about the YouTube video stabilization feature. If you are the type of person that takes a lot of videos with, say, your smartphone, then you'll be very familiar with the issue this feature is trying to resolve. Those shaky videos can be improved quite easily, although the processing time for your video may make you wait a fair bit to see the result. Nevertheless, results can be quite good and may help you get the most out of a seemingly poor video.