Talented local students. This is fantastic!

Talented local students. This is fantastic!
Twitter erupted in outrage over a seemingly "borrowed" cover version of Sir-Mix-A-Lot's "Baby's Got Back" on Thursday Night's episode of Glee, "Sadie Hawkins". The cover version arranged and performed by internet musician, Jonathan Coulton, applies an original folk music composition to Sir-Mix-A-Lot's lyrics and this music was apparently recycled note for note by the Glee music department without any credit. Since then, other artists are coming out of the woodwork complaining that Glee featured eerily similar versions of their cover renditions.
Here's a comprehensive article from CNN.
Check out the side by side comparison.
Do you think a cover version of a famous song should be protected by copywrite? Does it depend on the amount of original work is put into the cover?
This is a couple of months old but its still getting a lot of views on Youtube. This is British Pop star Tom Fletcher at his wedding in May. If you're getting married this is the way to give a speech at the reception.