Here are just my 2cents.
I still use my HD2 (with Android) and will do so until it dies. I have test driven the One X, which is an absolutely magnificent device and will be my replacement. With regards between Windows Mobile 6.x and Android, I prefer Android a million times more. It is maybe not so stable on the HD2 (keeping in mind the device was developed for Windows Mobile) but on the One X it is strong an stable and highly customizable. The only reason I would go back to Windows Mobile is for nostalgia and... well there is no other reason. There is nothing that Windows Mobile does for me ME that Android does not do as well and better.
I am glad that the hardcore Windows Mobile users still have Artemis although it seems it is coming to an end as its user base seems to drop. I am sure there will be many feisty "not true comments" to this but it is inevitable.
Anyway, just my 2cts.
best regards, Kuzibri - Artemis addicct since version 9!!!!!!!