NVIDIA has uploaded new 9.11.1107 version of PhysX System Software.
Official description does not provide any details about new features in this release (only support for “500-series GPUs” was mentioned – this is not new), but we have spotted updated .dlls (.41) for PhysX SDK 2.8.3 and additional PhysXCore.dll for SDK 188.8.131.52 in a separate folder. Apparently, there are some other minor bugfixes.
Also, PSS 9.11.1107 is included in new 285.79 Beta GPU Drivers (upd: actually, mentioned, but not included).
PhysX System Software 9.11.1107 is available for download from NVIDIA website.
Upd: According to several user reports, this PSS is working fine with Hybrid PhysX and mod 1.05ff.