You know, I have to say the popular spots in Taipei (at least Song Shan and Xin Yi districts) I've definitely seen a decline in people playing.
Yesterday, I had an afternoon to kill so I went around New Taipei City. to the Magnemite spawn, at 928 Memorial Park in Yong He and the Xin Zhuang Baseball Stadium, the Abra spawn.
The game is still going strong! At least in those two places they are!
The buddy Pokemon system has been announced by Niantic. I assume Taiwan will get the update within a day or two since it was announced last week.