After a few experimentation on Amazon EC2 and its new feature(Amazon EBS), I was able to share some tips for an EBS device formatted as XFS. Always make sure that the file permission belongs to the correct user(s) UID when you start using the mounted EBS device(unless of course if its a newly created/formatted).
Check this group for further discussion: http://groups.google.com/group/ec2ubuntu/browse_thread/thread/f44fb3ae0e068919
Thanks to Eric Hammond for posting my name on his MySQL Amazon EBS tutorial. http://ec2ebs-mysql.notlong.com