So Omnisphere has subtly hinted at a few things that I think may or may not happen in the future in regards to Spectrasonics:
The first would be Trilogy, which doesn't seem to have much info at this point. Of interesting note is that Bass Legends is not included in the Omnisphere library, I suppose that it is likely that we will see included in the library of the new Trilogy. I am still wondering whether Trilogy will be some sort of expansion pack for Omnisphere, or its own complete plugin. I am assuming that the interface will be very similar to Omnisphere, since they are both "Steam" engine.
Of even more interesting note is the exclusion of hearts of africa and hearts of asia (as far as I could tell) from the Omnisphere samples. Could that possibly hint at some sort of "ethnic lead" rompler in the future? I know that when I first bought RMX and Atmosphere I said I'd love to see an ethnic VI, I suppose if enough people said the same thing, they might give it a shot, who knows?
Finally, what can we expect to see in RMX 2.0? There are lots of interface updates in Omnisphere that can be directly ported. The entire browser could be reworked to line up more with Omnisphere. The modulation setup would be awesome to have in RMX as well. I will say that I absolutely LOVE seeing where the soundsources came from in Omni (and that is an understatement), anything like that for the percussion loops would be really cool, but that might be a stretch. Also the way that Omni handles host automation is the most brilliant thing I have ever seen. Spectrasonics VI's always lacked in regards to host automation capabilities and they leaped way the hell ahead with Omni's method.
Either way, I feel like I'm set for life with Omnisphere (could use a intel trilogy solution though), can't wait to see what they come up with next though!