It looks like Outlook Mobile may be getting threaded conversations in the form of emails in Windows Mobile 6.5.3. The feature, shown on video below courtesy of WMExperts, is not dependent on Exchange 2010, which was initially thought to bring threaded views. Rather, Outlook Mobile on 6.5.3 should natively be able to support threaded email messages from any account, including your plain GMail.

(via: WMExperts)