You have full control over what music, videos, photos and apps to sync to your iPhone, iPad or iPod touch. But you need to use the correct iTunes screens to set up these options or you will simply get the defaults. You can also control what gets automatically put on your iOS device through iTunes or via iCloud. Unless you turn off several options, you will automatically get new purchases when you sync or even via iCloud right after purchasing.
With "My Queue" you can quickly save videos to watch later.
To add an item to your queue just click the sign next to the video.
Once you've added a video visit "My Queue" to start watching!