Youtube gives you an option to subscribe to any channel updates and receive them on your homepage wall or email (weekly) if you like.
You can simply goto youtube and watch any users video that you want updates from and click subscribe button above the video on youtube, and it will be in your subscribed users list.
If you want to receive email updates whenever a youtube channel ads new videos to it (e.g hollywood channel ads new movie trailers or any other vidoe) follow this tutorial.
How to subscribe to youtube channel videos updates to your email
1. Sign in to your youtube account
2. Goto top menu > My Account > Settings
3. On left column select Email Options
4. On youtube email options page select Send subscriptions updates once each week
Now youtube will send you weekly subscribed channels and users videos updates summary to your email account.
Note: To get instant update to your email for video posted on youtube by specific channel follow this tutorial: Get youtube channel update by email.