It looks like LDOM 2.0 support will be included in the next Solaris update, update 9 probably planed for release around september. This will in practice mean that it will finally support dynamic reconfiguration of memory. It will also include cooperative domain migration support, which is a foundation for live migration, which at least early this year was scheduled for LDOM 2.1. This will be built on the next LDOM firmware, 7.2.10.
LDOM 2.0 will also support the next Niagara chip, the UltraSPARC T3 with 16 cores. When put together with the announcement that the LDOM team is hiring it sure looks like Oracle is investing in SPARC and LDOM technology.
Solaris Virtualization for Voice of Customer Tour (PDF)
FWARC/2009/452 HV APIs for cooperative guest migration
Talks I have given
3 months ago