Good news everyone! That had to just be a little publicity stunt. There's no other reason they would do it, really. They had to know switching voices would piss the fans off, especially Futurama fans for god's sake.
I was watching Major League 2 the other day and some of the players in that movie do some pretty funny/absurd homerun celebrations. Soriano was like Willy Mayes Hayes, except instead of laughing I wanted to climb through my TV and trip him as he was rounding 3rd.