On a related note, Hami is more than just an ebookstore. CHT launched it in 2008 and it also sells Android apps, music, and videos. I can't find info on the other content but it reportedly stocks 70 thousand titles from 250 local publishers.
CHT reports that they have over 1,000,000 ebook customers (about 4% of the population of Taiwan) who have downloaded over 6 million titles. They hope Hami Publisher will help boost the number of users past two million and cumulative downloads to 10 million by the end of the year.
On the other hand, Chunghwa Telecom is likely overly optimistic in their goals. They had previously planned to reach 1 million users by the end of 2011 but only accomplished the goal in late 2012.