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One of the main reasons I bought the phone was that I thought it would be upgradeable...

It's still a frikkin' great phone though, even with Windows Mobile 6.5

Glad I bought the Hero, especially now - free upgrade to Android 2.1 complete with SenseUI FTW.

There will be a WP7 ROM on xda when it's released.

Patience, young Padawan

Microsoft have said that no Windows Mobile 6 phone will get an upgrade to Windows Phone 7. They don't believe that the hardware on Windows 6 / 6.5 phones are up to running Windows Phone 7.

That said, I haven't seen any upgrades for any of my previous Windows Mobile devices, the answer from the manufacturer has always been buy a new one...

Its a shame because IMHO the HD2 is the best piece of hardware on the market. Would love to see it running android but there are some new HTC offerings comming soon.

Actually, the reverse is true. The HD2 exceeds the spec for a windows phone 7 device. The reason it won't get an upgrade is it won't be certified because it's got too many buttons, would you believe. The Windows Phone 7 spec requires three and only three hard buttons on the device and the HD2 has five.
of course, it's a scam. MS don't want to have to support their new OS on existing devices because they want to disenfranchise the manufacturers; essentially to turn them into grey box manufacturers for phones that all bear the 'windows brand'. They don't want you to buy a HTC phone or a Samsung phone, they want you to buy a Windows 7 phone.

Jon