My HTC HD2 is a trusty phone. It's been around for about 2 years now. Upon release, it was a monster and was one of the first - and even to this day one of only a dozen or so handsets - to support such a massive screen.
One of the reasons it's still popular in certain circles (the hackers/tinkerers/hobbyists) is how well it has supported modification over the years. I have seen it personally run Windows Mobile 6.5 (and many variants therein), Android (again, many versions) and Windows Phone 7 and Mango. I have also seen the interwebs do amazing(ly geeky) things with it too, like putting Meego and Windows 95 on it!
I run WP7 on it though, a Mango RTM version specifically. How excited I still am though to get the 'proper Mango' version, and hopefully before the more legitimate handsets receive it. The smugness one can have, honestly, you'd think I'd just bought an Apple product and was keen to argue about how amazing it is even though no one really cares only to find that I'd really just been trying to convince myself of its worth... woah, where'd that come from? Moving on....
Today I received the indication that a software update was due... oooh, could this be it? Certainly about the right time, no? Zune indicates the update is for "Mango ISV Beta Bundle: Cleanup" which made my heart sink a little. Probably not the release I'm waiting on then, but almost certainly a precursor to the update.
In short, the update takes less than ten minutes and does... absolutely nothing. Nothing perceivable anyway. No Mango update rolled in immediately afterwards either. OS Version reads in at 7.10.7720.68 but I honestly can't remember what it was prior to the update (oops).
Ah well. Can't be long now.
After comparing notes with a friend who has the Mango update via a genuine upgrade path (I.E., a legitimate Windows Phone 7 device) and comparing OS Versions, I think this cleanup was simply removing the RTM nature from my OS.
In other words, I believe this update brings the full juicy Mango to anyone running the RTM version. The reason there are no perceivable differences is obviously because not a lot / nothing changed between RTM and the final release.