Windows Mobile 6.5 is soon to become Windows Phone Starter Edition. According to Microsoft, this version of Windows Mobile will be stripped down to one of two versions. One with Office Mobile and one without (Office 2010 when it is officially released).

Currently it is believed that Microsoft will roll out Windows Phone 7, Windows Phone Starter Edition (stripped down 6.5) and possibly Windows Phone Classic (which has yet to be officially confirmed). Classic is still a rumor, but seems to be edging closer to reality as Microsoft prepares a complete revamp of its Windows Mobile line.
This move is very similar to Microsoft’s release of Windows Starter for the PC, which is meant for emerging markets and low end computing devices. Unlike the current Windows 7 PC platform, that is shipping the Starter Edition with low end computers in all markets, Windows Phone Starter Edition is going to be an exclusive for emerging markets only. This little fact is proven by Microsoft’s lack of support for the HSDPA 3G network.
Some details of Windows Phone Starter Edition include Office Mobile (only included in one version of WP Starter), 2.5G (CDMA2000 XRTT, EDGE, GPRS), CDMA (Rev A), TD-SCDMA radios and 2G (GSM) support. It is already confirmed that a number of OEMs are on board to launch devices running this edition of Windows Phone.
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I really hope Windows “Classic” ends up being Photon…
http://www.mopocket.com/2010/03/photon-the-windows-mobile-ui-that-could-have-been.php
I hope wm6.5 devices will get access to windows phone apps.