According to this Tech On! report, Nintendo are in the process of evaluating their Wii Remote accelerometer technology. Seeing if other companies can supply better gear than their current suppliers can.
One firm - Kionix - definitely can. Currently, the Wii Remote's accelerometer sensors are provided by two companies: Analog Devices and STMicroelectronics. But Kionix employ different technology, which makes it "easier to enhance sensitivity".
You enhance sensitivity, you enhance accuracy, and your games get more precise. And, hopefully, more enjoyable. To this end, Nintendo have been evaluating samples from not only Kionix, but other firms as well, although no cold, hard decisions have yet been made.
Know that this is the tech for the standard accelerometer in the Wii Remote, not the Wii Motion Plus.
Competition Heating Up for Wii Acceleration Sensor Contract [Tech On!, via Wii Fanboy]