Everything gets fed to it via a playlist array. So you can send a bunch of videos to it and play them sequentially or skip through them using the menu bar. Plus you can mix and match types.
Easy to set up
That top demo just uses a link field. Just install the player, add a link field with unlimited values and set the display formatter for Projekktor...then link to whatever. It could be YouTube path (embed or watch), a remote file, or even a local file.
The links I used for the above demo
http://www.lunarclips.com/sites/all/libraries/projekktor/media/intro.mp4 http://www.youtube.com/watch?v=yLdZd7Z37lM http://medias.jilion.com/sublimevideo/dartmoor.mp4
And as you can see, it can display and unlimited number of players on a page. Each player can have different options and dimensions.
Projekktor plays well with views fields. Current integration allows adding "file" types to views data (such as media module, media: youtube, or standard file fields). Your view will utilize one video per node and combine them into a playlist.
So if you already have a bunch of YouTube content on your site in different nodes you can pump it all into a Projekktor through a node reference. Just install the module and set the display format to "Projekktor".
I'm currently in the process of integrating jCarousel support to take advantage of Projekktor's playlist functionality. Other eventual improvements include enhanced views support and WYSIWYG support.
The module is currently alpha testing and appears to be quite stable. By all means please toy with the module. Looking forward to hearing back from testers.
It probably works with lots of others too. I haven't tested them all yet.
PS: I'm working on getting it up and running in an overlay like in the Imageflow demo.