According to IGN, don’t expect an updated version to the 3DS like the DS received.
Shigeru Miyamoto told the company that Nintendo is working on the successor to the 3DS instead of an upgrade that would include both analog sticks, or other features.
“I really feel like I’m satisfied with the 3DS hardware as it is. I feel like it’s the best for this generation,” Miyamoto said. “What we’re thinking about right now is probably going to be for a future generation of handheld.”
Miyamoto added that the 3DS’ gyroscope could help accommodate adding a second Circle Pad to future 3DS systems.