In addition to the Xda mini S confirmation, Gears also confirmed that O2 UK will definitely carry the Samsung SGH-i300 Windows Mobile Smartphone which O2 UK announced earlier but which was delayed (original launch-date was expected for October) and is still listed on O2's online shop to become available in December 2005.
However, in the same flyer where the Xda mini S appeared, O2 UK also lists the Samsung i300 now.
Beside O2, I'm not aware of any other carrier yet who might carry the i300 also. Don't know if it will goes on sale as an O2 exclusive device but so far, only O2 Germany and UK has announced it.
Cheers ~ Arne