The HTTP response headers suggest that the page was last modified on 2009-09-30. Since then, SHA-3 (Keccak) has been finalized. Be that as it may, I'm curious

The HTTP response headers suggest that the page was last modified on 2009-09-30. Since then, SHA-3 (Keccak) has been finalized. Be that as it may, I'm curious about the recommendation to use WHIRLPOOL. If anyone knows why this algorithm is supposed to be better than, let's say, SHA-512, I would appreciate an explanation. Is it because of some intrinsic strengh of the algorithm? Is it because one of the authors is Vincent Rijmen of AES fame? Is it because NESSIE is more trustworthy than NSA/NIST? Or is is simply because no one has found a way to break WHIRLPOOL yet?