Superfud
The fact that change ID is stable is very convenient for humans - means you have something explicit to hold on to as everything else may change over time.
Then when you have the changes lined up you --amend that same commit.
Where you'd really see benefit would be when you have multiple config files (with database credentials and addresses, for instance) that vary per server and environment involved. In addition, if you need to run post-deploy actions such as building assets, or run database migrations, a tool would help you.
However, until you feel the pain of your current setup, no need to change what works :)
Other benefits of the tool include putting all config files into version control, and a lot less less magic in your deployments.
Modernize Your Git Workflow
The sneakernet in git - trivial backup of personal repositories
Identify what your Ruby process is doing
Ack Effortlessly search your codebase
Chop – efficiently dispense with the current git branch
Quick data import and linking in Rails
Easy local code-review with git
Simple git workflow with hack and ship
http://object.io/site/2010/12/hack-and-ship/
Branches are virtually free with git, it makes a lot of sense to create short-lived feature-branches for each new thing you start working on. This does mean a bit of shuffling back and forth to integrate changes from others in your local work, but this “pull changes and rebase my work” workflow can be greatly eased by these small scripts.