Windows Phone 7 or Android for Horde, Lightning and mobile phone synchronization?

Starting fresh with Windows Phone 7 was a bold decision on behalf of Microsoft. Whether it will be a successful one remains to be seen. Being an old Windows CE, Pocket PC and Windows Mobile user about to buy a new phone, I have been waiting for WP7’s release eagerly.

I have been reading and trying everything I can put my hands on and I still can’t decide between Windows Phone 7 and Android (yes, iPhone is out of the question). Available applications are of course going to make a difference in the early days, as every major application is soon going to be available in every platform.

My real problem, though, is how to synchronize my contacts and calendar among my new favorite PIM, Mozilla Thunderbird + Lightning (on my way to Linux), my new to-be phone and, ideally, my personal cPanel-based cloud, Horde, without using Google Contacts and Calendar.

This is what the decisive factor will be. I am open to suggestions.