I already knew that the [tag]FIRST LEGO League[/tag] would be allowing use of both the old style Mindstorms RCX and the new NXT in the coming season. But since the NXT uses different sensors and motors, the question of backward compatibility has been an area of much speculation in the online [tag]LEGO[/tag] forums such as the LUGNET Robotics group. According to my source, LEGO Education will offer a cable that can connect legacy Mindstorms sensors and motors to the new NXT. He didn’t have specifics about the electrical connections, but it would be a cable that had the 2×2 brick connector used by the current Mindstorms on one end, and the offset RJ12 connector used by NXT on the other.
Also I was wondering about the ongoing life of the original Mindstorms once NXT is available. He was surprised when I told him that LEGO Shop-at-Home has already discontinued their Mindstorms Robotics Invention System kits (which include the 2.0 version of the RCX) but he assured me that [tag]LEGO Education[/tag] will continue to sell their Mindstorms sets (which use the 1.0 version that has a 9V DC power port), even after the NXT becomes available. I believe this is to avoid forcing teachers to replace their entire inventory with NXT sets.
Also, I asked about the power adapters for the NXT bricks. He said that there will not be a power adapter port in the NXT sold by LEGO Education, but that they would offer a special rechargeable battery pack which can be used instead of the usual 6 AA cell batteries. Teachers and AFOL’s who love the power port will be disappointed by this news, but at least the battery pack may have better life than the equivalent set of AA batteries would.
Finally, he confirmed that the NXT units can talk to one another using Bluetooth (but not using USB, as the NXT’s USB port is “slave only”), and that they will have a single address space rather than the current RCX design which segments the memory into five partitions for different programs.