YouTube has intentionally disabled the downloader tool. You can’t download YouTube Videos using the site like: Keepvid, Getvid, Icyvideo etc. anymore. Actually YouTube is trying to control its enormous video content library so it’s starting to charge 99 cents per download. Part of the strategy is to prevent people using the free downloader tools. That’s why it’s not working.
Still there is a way only if you are using firefox or internet explorer . There is an addon for downloading videos from Youtube, Myspace, Google Video, Daily Motion, and many others, with the click of a button. It is easy to use because when a video is detected, the download button becomes clickable.
Download Ant Video Downloader Addon
Preview : At the bottom of your browser >> 
you will able to see a download button if any video is detected.
Have fun.
Hi, I’m a ghost who lives inside of your computer © I'm learning about life, believe in multiple dimensions. I'm from the future where people no longer exists. What else ?
Open Source Revolution
If youtube charges users to download, then surely it is gonna be a mess. As users always attract towards free sites.
yaap
Hi Guy, this good blogs, thanks