Well, that's somehow interesting. While the P3600 (aka HTC Trinity) isn't on HTC Europe's list of devices which deserves the Windows Mobile 6 upgrade, in Australia, HTC launched a Windows Mobile smartphone called P3600i which is a feature-upgraded P3600 and even includes Windows Mobile 6 Professional.
Beside all the other P3600 goodies (like quadband GSM/GPRS/EDGE, UMTS/HSDPA, Bluetooth, WiFi and the 2 megapixel camera), the P3600i sports an improved 500 MHz Samsung chip and 256MB of ROM (while the P3600 "only" featured a 400 MHz Samsung chip and 128 MB of ROM):

The HTC P3600i is already available from 3 Australia and costs, without a subscription around 622 Euro/US$ 839.
No information available yet, if HTC also plans to release the P3600i in EMEA as well or if it is a APAC only offer.

Cheers ~ Arne