I just purchased a copy of JomSocial professional edition, and I want to have a comparison between jVideodirect and JomSocial video component. So far, I have no idea which one is better. I am looking at: extensibility (such as multi-server support for future growth), stability, functionality (SEF url rewrite?), and user experience.

I would appreciate any suggestion or discussions. Thanks!

Currently, JVD is still on beta. We are approaching stable very soon.
With the version 1.1 which release in early Nov, there are many fixes and resolved many compatibility issue. Apart from what you see in the main page description and demo, JVD will have major sef component plugins available together with Version 1.1 or you might use joomla built it sef solution. in terms of multi-server support, depending on which layer are you referring to. If you are talking about 1 server for rendering display, 1 server for conversion processing and other for storage. Currently, this is not an option yet. however it is in out to do list.