I can confirm that the OTA-update for the Sensation works. It is indeed 200+ mb instead of only the updated files, but it works like it should! I've still got all my data and I made and restored no backup.
@Mark, is it possible for you to add build-numbers to the filenames? That way we can see easily if there is a new version available (2.4.27.1 and 2.4.27.2 for example).
The Miui-updater on my phone alerted me that there is an update available to this weeks version. Can I install that update or will everything be in Chinese then?