Yep, Samsung in their wisdom disabled them , you can get smaller updates (IIRC there was one for Camera Firmware when I got my S2) but full firmware has to be done via Kies , on a PC - there is a Mac version of Kies but it doesn't support firmware updates to Android , only BADA I think. Thus leaving anyone without a windows PC completely unable to upgrade , cool eh?

Pretty unforgivable in the best of circumstances , but to actually REMOVE existing functionality to achieve such a state is bizarre !