If you’re an owner of a HTC Desire Z from Vodafone, you can now update your device from Android 2.2 to 2.3 via an over the air (FOTA) update. Your device will periodically search for the update and then ask if you’d like to download (do it over Wi-Fi!) and install the 104MB update. If you’re not a fan of waiting around for the update, head to the settings menu of your Desire Z, hit About phone, then hit search for updates; the phone should then download the update.
To answer the question a lot of people ask us when updating: no, you will not lose any of your songs, photos or whatever from your MicroSD Card, but we suggest backing up your SMS Messages just to be on the safe side. You can do this by using an application like MyBackup. Good luck and let us know how you go in the comments!