not all the aspects of FlyAKite work on vista. For example, the window blinds skin, the cursor, object dock work. On the other hand, the tiger system properties,icolorfolder dont work.
They shutdown the FlyAKiteOSX project last year and now even their official website is down http://osx.portraitofakite.com/
Personally i think its better to manually tweak windows to look like a mac because firefox can be a huge memory hog. Also you can even make windows look like leopard if you go for the manual method - which involves software like window blinds, object dock / rk launcher, iconchnager.
http://www.osx-e.com/ has some pretty good collection of mac emulation (aka lookalike) software