when is a cover not a cover?

What are the rules on "cover" songs? 'Cuz I was watching America's Next Top Model last week (not that I watch that show) and was surprised to see that the models were part of the music video for "Enrique Iglesias' new song, 'Tired of Being Sorry.'" Whaaa...? That's not an Enrique song, that's a Ringside song!! They didn't give any credit to Ringside - no indication that it is actually a cover. And the original is so much better than that cheap, crappy imitation! Grr. I'll let you be the judge (but if you don't say Ringside, you're crazy). Here are the options:

Ringside version
Enrique version

While we're talking about music, Emily pointed out this fantastic music video for fantastic Andrew Bird's fantastic song Imitosis:



I hope he comes back to the DC area soon. I want to see him in concert again!!