I just realize that wordpress 2.7 that I install yesterday has other great feature :
Core Update
This feature need cooperation from your host, I’m lucky my hostmonster account support me well.
To apply it just click ‘stay updated‘
It will automatically download and install :
Upgrade WordPress
Downloading update from http://wordpress.org/nightly-builds/wordpress-latest.zip
Unpacking the core update
Verifying the unpacked files
Installing the latest version
Upgrading database
WordPress upgraded successfully
Click on dashboard to see current version of your wordpress :
To see list of webhosting that support it ( at least reported work ) you can visit Core Update Host Compatibility at codex.