I found out the jetBook is also in China, called the Dr. Yi. (I don't, however, know if this means the jetBook is of Chinese creation. But I wouldn't be surprised.)
Of particular interest to me is this:
CPU: ARM9 200MHz
Because look at this for the Sony Reader 505:
CPU: Freescale i.MXL, ARM920T core, 150-200 MHz
That says to me the jetBook should have the horsepower needed to deal with ePub files. I had been wondering about that.