No, I don't have the Flashback Trojan :)

$ defaults read /Applications/Safari.app/Contents/Info LSEnvironment 
2012-04-09 22:25:03.515 defaults[35678:707] 
The domain/default pair of (/Applications/Safari.app/Contents/Info, LSEnvironment) does not exist
$ defaults read ~/.MacOSX/environment DYLD_INSERT_LIBRARIES
2012-04-09 22:25:12.324 defaults[35679:707] 
The domain/default pair of (/Users/myUserName/.MacOSX/environment, DYLD_INSERT_LIBRARIES) does not exist