My on-line upgrade from Feisty to Gutsy got aborted by intermitent internet connection. Overall upgrade seemed to transform into installation of some adidtional 1200 modules. Finally got them installed.
However, NVidia drivers did not work (used the Envy package successfully to solve that problem); next I'm trying to solve problem of microphone not working. Not all of new desktop enhancements are operational, but that is not a big deal.