System X? You mean are they cross-compatible?
The TI2 can do everything that the Virus B can do and can load all Virus B sounds and also be controlled by Virus B. But if you try to do vice versa (load TI2 sounds into Virus B) given that the Virus B doesn't have many of the newer features of the TI2 a lot of parameters will either be ignored or alter existing ('classic') settings. The features that are 'classic' will still be transferred, but you'll just miss all the newer oscillators (Hypersaw, Wavetables etc.), filters like the Analog filter, Vowel, Comb, multimode Vari-Slope and X-fade algorithms, the additional modulation source/destinations, modulation/step sequencer, Atomizer, and the stomp-box Overdrive/Distortion effects, Tape Delay, additional Character models, and two additional EGs, and maybe some other stuff I can't recall that the TI can do but the Virus B can't.
PS > And another thing! Will the Ti|3 have user customisable/importable wavetables?
A ribbon-controller or XY-Pad might be nice, too, please! Thanks!