i dont even have to click the link
Vista will not run on the PSP, mabye (and i stress mabye) a hacked version of XP would if it was severally slimed
there is simply not enough CPU for vista on the PSP, in any shape or form
however i did click the link and i quote
Instructions on how to install a PDA style Windows Vista interface on your Sony PlayStation Portable
its just a windows mobile hacked lookalike for the PSP, nothing special