Unfortunately it's true. I just passed through Hanoi airport coming in from korea last week, Immigration for all passengers required both index fingers to be placed on a reader and in front of a camera. Then the picture is compared with your passport pic, not sure what happens with the finger prints but guessing they are correlated. In addition, going into Korea the same thing except it's the index finger on right hand put into a reader and you do the same when leaving the country. They are definitely moving to the next level on tracking you.