Page Rankings Updated in a weird way

Hey I saw some changes on my page rank, but before this happened I had four or five days where my sites kind of disappeared from Google until they got back to their old ranks with new Page Rank, is this normal?

Thanks,

 

I think ur domain got slapped from google

 

Hi,
i think some change on your site structure and content and doing quality back links.

 

I'm not sure with this.. but i think it's somehow related to Google Dance..