While Amazon clearly controls the e-reader space, Barnes & Noble continues to beat them to the punch on key technologies. First, it was an Android-based color tablet. Then it was the front-lit e-ink reader.
Amazon has to react, probably faster than they’d like — they’re pushing out a new Kindle not even a year after the last one was released.
Update: As Soroush Khanlou points out, B&N did the touch e-ink reader first as well.