EA has released an interview with producer Greg Kasavin on the build mechanics of the different factions, primarily the EOTRS. Here's a piece:
1. When creating Red Alert 3, was it decided early on that each faction should have a different build mechanic?
GK: Yes, we were interested in the possibility of each faction having a unique build mechanic relatively early on. However, what was more important to us was to wind up with three factions each with a different and distinct feel to them. The need to come up with different build mechanics that played into each of the factions' identities naturally emerged from that goal. In the case of the Empire of the Rising Sun, we wanted to come up with a fast and flexible build mechanic that supported the faction's ruthless nature and predisposition toward hard-hitting, unpredictable assaults.
2. What opportunities does this build mechanic give players?
GK: The Empire of the Rising Sun has the most unrestricted base-building mechanic, so it presents a lot of interesting opportunities for aggressive, sneaky, or creative players. Rather than have to build structures next to their Construction Yard, the Empire builds these hovering robotic vehicles called Nanocores, which can go just about anywhere before "unfurling" into a specific structure. So you can spread your whole base out across the map, park your structures on the enemy's doorstep, and much more. It's also relatively easy to expand to additional resource points as the Empire, since all they need to do is drive a Refinery Core over to an unclaimed Ore Mine. Even better, their Ore Collectors can defend themselves using concealed autocannons.
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