Kaltura is an open source media platform, which allows registered, both paid and free, to customize and embed the player portion of a video rather than the video itself. The player of an embedded video is the "console" which allows you to change the volume, resolution, time and other various portions of a video's settings. 

One main advantage of Kaltura is that it is based on a creative commons license, and being open source, it allows a lot of customization  as well as allowing those with limited funding an easier way of sharing their videos professionally. Where sites like Vimeo and Youtube are video hosting sites, this is simply a site which helps with customization of videos to use on other sites. 

However, the possible downsides to Kaltura include the system to have flash, which is usually not an issue but in some cases it might be. The system can be a little difficult to learn quickly, but once the user understands how the platform works, it is easy enough to use.