Very, very impressive.
The only stumbling blocks i encountered were issues with Active Sync which existed before I installed BirdieSync, but having worked around those issues already, I was able to do so again.
I have a habit of keeping my Thunderbird contacts solely for email purposes but keeping my snailmail address and phone info in Outlook 2003 (because it allows me to sync my contacts with Plaxo.com.) Plaxo recently released a wireless sync tool for Windows Mobile 6 as well.
This is joyously strange to me: I'm able to sync my Thunderbird address book, Outlook 2003 and Plaxo.com to "Contacts" on my AT&T Tilt / HTC 8925 without any negative fallout (or none that I've noticed yet.) I've got 275ish contacts, and I've not seen any duplication or problems.
And since I use Provider for Google Calendar to keep Lightning synced with several Google calendars, I now have access to my calendars on my desktop (and laptop) via Lightning, on any 'net connected computer via calendar.google.com and now (thanks to BirdieSync) I've got access to my calendars on my Tilt, even if I'm way out in the woods far from any cell or wifi signals!
Since I'm an IMAP user I don't need to use BirdieSync for mail syncing, but it is nice to know that if any of the mail servers I use have troubles, I can sync mail from my PC to my Tilt just in case.
The way things are looking at present, I'll be registering a copy of BirdieSync before my trial period is up!
Great work! Thank you for this.
Peace