Well it is long overdue, but Digital Aquatics is going to be releasing some new items very soon, perhaps as early as April. They should have several new items on display and working at MAX up in Costa Mesa April 5th and 6th. They are working on a new probe module that will have multiple BNC ports that will be programmable for whatever you want between ph and ORP. The new system will be switchable between 0v - 10v DC control and PWM control. It will probably have portions of it available for open source programming while still preserving the integrity of the critical firmware. They are talking about web based software control and built in WiFi and ethernet. Updating modules without disconnecting them, along with a few other things that they should have done from the beginning.
Stay tuned. And yes, the new stuff will all be backwards compatible with the current RKL and RKE modules.