These look to be official Muppet videos. Will there be a Muppet film coming soon? They are all over Youtube as well. Each character has just one video with limited cross linking. I look forward to seeing if they continue with this or if it's leading up to some bigger Muppet related announcement. Considering the amount of cash Alvin and the Chipmunks made recently Disney would be stupid not to pump out a new Muppets movie.
These videos are not only fun but right on the Muppet brand. It's extending the Mahnahmahnah! song which went mental when I was in highscool. It was on the Triple J Hottest 100 or something.
There are quite a few Muppet Videos done by fans. Plenty of gansta rap videos and movie mashups as seen below.
My fav Muppets were Beaker and the Swedish Chef.