The KDE project uses libssh for their kio_sftp implementation now. The new kio slave based on libssh will be released with KDE 4.4.0. As the implementation works fairly well, openSUSE has backported the patches to their KDE 4.3 release which is available in the openSUSE Build Service and will be released with openSUSE 11.2. More features will be added as soon as libssh 0.4 is released. The first release candidates will follow soon.
With the help of the KDE Team we have official support for Windows and MSVC now. The KDE Team checks regularly if the latest development version compiles and works. We will offer this support with the upcoming release of libssh, version 0.4.