Thomas Theiner - an Operations Manager product team program manager - revealed that the next version of System Center Operations Manager has been code named "Katmai". Baelson Duque, another program manager of the Operations Manager team confirmed that this is the correct code name, but did not confirm that it would be named Operations Manager 2007 R2.
While the release will not happen this year anymore, there is a good chance that it will follow-up the SCOM 2007 product next year. Unfortunately I cannot comment on the major changes (I am under NDA for this), but they certainly focus on key areas like Notification and Network Monitoring. Thomas did mention one thing that will be fixed in the next release; editting of the reports outside of the Console (using the SRS website) will not break the reporting functionality anymore.