7 Application Deployment Best Practices

1. Keep the installation structure SIMPLE. 
2. Always get rid of old files. 
3. Automate it 
4. Don’t over do it with the symlinks
5. Delete everything first. 
6. Have a roll back strategy.
7. Don’t make changes to your deploy mechanism or deploy scripts between deploying to different environments. 

http://java.dzone.com/articles/7-application-deployment-best