I don’t know, maybe we should take a vote, or a poll. I personally like both tools. You can actually use them simultaneously. Here’s how you can use both tools to make each one more powerful than it is on its own.
Upload a YouTube video. Then, send out a Twitter message with a link to the page for that video.
Another way, you can upload the video to YouTube then blog about it on your blog, embedding it there. Then send a short message on Twitter with a link to your blog post.
Here’s a Ron Paul video I Twittered a few moments ago:


