Rationale behind preference of AES over Blowfish

I have read somewhere (don’t remember where) that LibreOffice used to encrypt password protected files using Blowfish. But since 3.5, LO uses AES to encrypt the documents. Why was Blowfish ditched in favor of AES? I thought Blowfish makes it difficult to brute-force passwords by making initial key setup very expensive which would mean more security. So in my mind, that makes it better for security.

So, Why AES over Blowfish / Two-fish? Is this due to recent processors supporting AES ? Is this move to improve performance?

The LibreOffice 3.5 Release Notes say that AES-256 is more secure encryption algorithm than Blowfish. You can find some reasoning behind this in the linked Wikipedia articles.