If you're like me, then you probably spend a lot more time than you should on YouTube. Wouldn't it be great if you could download your favorite videos and watch them offline too? Sure, there's always the popular Firefox Download Helper plug-in, but how about an official solution from YouTube? It's here. YouTube will let you download certain Public Domain or Creative Commons-licensed videos.
Eligible videos will have a "Download this video" option underneath the video. YouTube videos will download in the MP4 format and are--thankfully--DRM free. Not all of the videos are free of charge, though: You will have to pay for some videos through Google Checkout before downloading them. Purchased videos will appear in your YouTube account in a new "purchases" tab under "My Videos". However, videos that you have downloaded for free will not appear in your account, which could make it difficult to find your content.
So far, I have not found any videos that require you to pay for the download. In fact, I have found very few videos available for download at all. Mostly, what I've found that is available for download is political and educational videos. I'm sure that Youtube will open up more as it finds more Public Domain videos, but right now the selection is limited. Sorry YouTube, but it looks like third party plug-ins are still the way to go for now.