Pandora app - can't find on app store?

Iphone 3GS running iOS4

I have searched on the app store on my phone for the Pandora radio app but can't seem to find it at all!?

Have they taken it offline because I can't see any trace of it ever being there. Also I have searched for it on the internet, and then click on the download link (which takes you directly to the app store on the iphone) and it says "Your request could not be completed".

Anyone got a solution for this?
Thanks