Well, I read a post on a newsgroup about an MU1000 and an MU2000, presumably the next generations of the MU128 module. It would be nice to know more about these modules, because the features and sound sets implemented on them might well be destined for an arranger keyboard. However, it seems the information on these modules is only in Japanese. For example, Yamaha has had a web-based FAQ on these modules since last year in Japanese. And even tho Yamaha Japan has an English version of its webiste, the info on these modules is omitted. I presume other products are also presented in Japanese and not in English.
OK, I understand that manufacturers and retailers do not want us looking too far ahead for fear will will overlook what is presently available. However, consumers do want to know what is coming so that they can make better informed purchasing decisions and because the future is fun! So if anyone can help with the language barrier, we could get some more information on future Yamaha products outside of Japan.
My understanding is that these modules use SmartMedia cards for waveform expansion, as does the already available S80. Thus, it looks like Yamaha may adopt SmartMedia as the portable medium of choice for its synth products. It would be nice if SmartMedia would be used for both styles and waveforms for future arrangers.
These modules, I understand, also use a USB interface for transferring midi and audio data. How well USB serves the purpose is debatable. However, the trend to provide direct digital audio connections is welcome.
In this regard, I also note that Yamaha is promoting the mLan standard, which is to be adopted on the new Korg Triton Rack. The mLan standard uses the 1394 (aka Firewire, aka iLink) standard for midi and audio data transfer. Devices can be daisy-chained. Given the amount of data arrangers can generate, mLan would be an appropriate addition to high-end arrangers.
I would appreciate others' insights on possible future developments.