I just don't see the point. You were annoyed by videos opening in a new window, so you made a plugin that opens the video in a new window that has less functionality.
This doesn't resolve your original reason for creating the plugin. A scenario;
Bob: Hey, George! Check out this video!
Bob:
You must be registered to see links
George: OK, one sec.
Bob: You'll like it haha
George: Wow that was cool! This reminds me of another video, let me find it...
George now has to close the window your plugin caused to open, then open a web browser, navigate to youtube and then search for the video he is looking for. Your plugin creates more work for most users and doesn't solve the issue you intended to solve.
The solution to this would be to open the video directly in the Skype conversation, or through a window that is "glued" to Skype in some way, with options to open the video in a web browser. The video would then automatically minimize back in to skype, essentially disappearing. This way you view the video with no annoying popups and the window management is handled for you. See below for an example,
Your idea is good but the execution is flawed and doesn't address the original issue.
Original Problem: Videos, when clicked, open in a new window and interrupts the Skype conversation.
Your Solution: Videos, when clicked, open in a new window and still interrupts the Skype conversation. Users are now unable to see related videos and are limited to the YouTube functionality shown in the YouTube video wrapper. If users want to see related videos or search for other videos, they now have to click on the video title, thus opening a third window and causing further screen clutter.
You've made the problem worse with your plugin, not better. I'm not being rude, I'm just addressing the facts and trying to understand why you thought this was a solution to the original problem.