The following criteria has to be met:
- stable release (>= 1.0)
- strong community (e.g. lots of forum posts)
- active development (new releases coming out reasonably often)
- good documentation
- important: support (plugin, library, component) for embedding videos (videos will be hosted on local server, not on public video service provider). External component can be used.
- preferred if it's based on PHP, Java, Ruby, Python