Also installed first few days to test it out. Not seeing too much difference from 5.0, little benefits here and there...
Noticed that the support site is now https://support.ptc.com/help/creo/creo_pma/r6.0/usascii/ instead of http://support.ptc.com/help/creo/creo_pma/usascii/, funny that it's r6.0 instead of 184.108.40.206? 6.0 F000? I dunno what the numbering scheme is anymore these days 😛
Biggest change that would benefit us is that this fixes https://www.ptc.com/en/support/article?n=CS272510, which fixes cross sections causing annotations to throw warnings when an annotation references a section and that section isn't active. If you haven't yet noticed that 3D section references break in Creo 4 or Creo 5...well, best you check now and evaluate whether 6.0 is an option.
The integrated help in the UI is also a nice plus.