Currently, the Cyburbia Forums are based on vBulletin 2.3.0. The next release of vBulletin will be version 3.0, which is already in beta testing by many sites. vBulletin 3.0 promises many improvements and new features, which I won't describe here.
When will Cyburbia implement vBulletin 3.0? It'll be a while after it is released. The 3.0 database contains many new, renamed and altered tables, and some of the programs that rely the vBulletin database (PhotoPost for the Gallery, for instance) may not work properly with 3.0. Once these programs are updated to use the 3.0 database, the Cyburbia Forums will make the switch.