Get it here: http://www.softimage.com/home/downloads
The bugs fixed in 5.0.1 are as follows:
UDEV00191845 XSI crashes with a Chinese or Korean Windows OS
UDEV00192168 Seams effect of Toon_Paint_and_Host does not work
UDEV00190523 Crash when exporting to mi with subdivision geometry shaders enabled
UDEV00190865 Rendering | Incorrect version of character in mi file when objects are subdivided
UDEV00191137 DirectX9 | Strips of geometry are missing when rendering with directX
UDEV00192377 Binary characters sometimes appear in particle cloud material names
UDEV00192992 2D_Fur shader goes into infinite loop when rendering
UDEV00193378 Export MI2 broken + multithreaded broken
UDEV00186773 Filtering values do not visually update
UDEV00193281 V5 cannot render certain 4.2 scenes
UDEV00193304 Deform Motion blur seems out of frame/step with Regular MB