Since I have a Brewtroller as my build's heart, I'm glad to have seen some news just added, introducing the new 3.0 version.
Copy&paste from this official announcement.
Flexible System Support: BrewTroller 2.x is designed for three vessel systems. A number of hacks have been introduced to support systems with 1-4 vessels but they are hacks. BrewTroller 3.0 will allow up to five vessels in a system. Roles will be assigned to vessels and used in the brewing logic. Those roles are: Strike (Heat), Sparge (Heat), Mash, HEX (Heat Exchanger), Boil. A single vessel system would consist of one vessel that is assigned the Strike, Mash and Boil roles. A typical three vessel system would assign the Sparge/Mash/Boil roles to the HLT/mash Tun/Boil Kettle respectively and either assign Strike to HLT or Mash Tun depending on the brewer's preference. A HERMS system assigns the HEX role to the HLT or a dedicated HEX vessel. A RIMS system would use four vessels with the RIMS tube acting in the HEX role. SMART_HERMS_HLT logic now becomes part of the HEX vessel and could also be used with RIMS systems.
Flexible Output Support: With flexible vessel support comes more flexible support for outputs on your system. Instead of hard coding vessel heat to specific outputs you will simply select the output to use for PWM Heat (ie PID Mode) on a vessel or configure the Vessel Heat/Idle Output Profiles to operate a burner. This means we can distribute a single firmware for say the OpenTroller BX1 instead of distributing Single Vessel/HERMS/RIMS versions for each. The new output logic presents outputs as a series of output banks allowing for a combination of built-in and add-on output support.
Pre-compiled Firmware: No more Arduino IDE to download, libraries to update or compile options to configure. Instead all configuration is moved to the user interface (UI) and firmware is distributed as a compiled HEX file. The code is still open source but only those who want to contribute to the development need to download the source code. The firmware can be uploaded using a command line utility (avrdude) or ideally through a GUI for avrdude. And while we're discussing ideal scenarios I'd love to see a GUI that allowed backup/restore of system configuration and (let's set the bar high) handle migration of configuration settings from one version of the firmware to the next.
RS-485 Support: You may have noticed many of the OSCSYS devices include RS-485 Serial Ports. This will become the standard way of expanding OpenTroller systems. It can be used to add outputs to the DX1/BX1/EX1 platforms. It can also support mounting the bulk of your control panel on the wall or on your brew stand and presenting only the LCD/Encoder, RGBIO and PID Display modules as an operator panel connected via a single RS-485 cable."
To me it seems quite interesting, especially since I was already planning to add a fourth kettle, dedicated to the HERMS coil!