Mail 5.0 in OS X Lion has some new animations when you send or reply to an email. If you find these distracting, there is a way to disable either one or both animations without having to revert to the classic layout.
1. Close Mail.
2. Open Terminal.
3. Execute the following Terminal command to disable the Send animations:
defaults write com.apple.Mail DisableSendAnimations -bool YES
4. Execute the following Terminal command to disable the Reply animations:
defaults write com.apple.Mail DisableReplyAnimations -bool YES
If you decide you want to them back later, you can enable the animations by executing
defaults write com.apple.Mail DisableSendAnimations -bool NO
and
defaults write com.apple.Mail DisableReplyAnimations -bool NO
