I use Xmarks for more than 3 years, but just received the following letter:
Dear Xmarks User,
We've always said we won't email you unless it's important; this is one of those occasions:
Xmarks will be shutting down our free browser synchronization services on January 10, 2011. For details on how to transition to recommended alternatives, consult this page.
For the full story behind the Xmarks shutdown, please read our blog post.
Thank you for being a part of the Xmarks community; we apologize for any inconvenience this step may cause you. We believe we have the best users in the world, and we hope your bookmarks and find a new happy home soon.
— The Xmarks Team
The question of the community — that can be used for synchronization.
— Synchronize passwords and tabs (safe)
— Availability profiles
— Synchronization between Firefox, Chrome, IE, Safari
— Work on platforms WinXP and MacOS 10.6