Kind of, but……
Here is the legal answer (per YouTube):
“You retain all of your ownership rights in your Content. However, by submitting Content to YouTube, you hereby grant YouTube a worldwide, non-exclusive, royalty-free, sublicensable and transferable license to use, reproduce, distribute, prepare derivative works of , display, and perform the Content in connection with the Service and YouTube’s (and its successors’ and affiliates’) business, including without limitation for promoting and redistributing part or all of the service (and derivative works thereof) in any media formats and through any media channels.”
In short, you own your masters, but YouTube can do what they want with your video.
Users should keep in mind that YouTube allows others to download your videos for personal use. If you do not want people to download your video, please disable that option. In addition, users should also be aware that the terms and agreements may change, and you as a user agree to accept those changes without prior consent.
Also note that if a person has uploaded your personal copyrighted material (registered or not) you can request for YouTube to take it down. Here is that link.
My Recommendations: I would only use YouTube for promotional content, educational purposes, video blogging, and advertisement. I would not suggest you place anything on YouTube that is propriety. Do not upload any videos relating to inventive concepts, such as ideas that are suitable for patentability. You may, however, upload your videos that has your trademark. You may also post your copyright material on YouTube, but note, that your copyrighted material must be registered with the Copyright Office before you can file an infringement lawsuit.
Here is the link to YouTube’s terms of service.