Come back? What do you mean, come back!?!? Hokkien may be losing ground to Mandarin, but soooo many people still speak Hokkien compared to Mandarin (although the gahmen would like us to think otherwise...)
However, seeing as they would be declaring themselves wrong which would lower the population's confidence in them which would reduce S'pore's ability to compete in the global market (or at least that's what they'd say rotflmao) then I doubt that'll happen any time soon

In Vietnam, most Chinese are Cantonese if I recall correctly with a smaller percentage of them being Teochew.
ppk: czr:
Well no, actually, if I recall correctly, Teochew IS a Minnan dialect. MIN dialects have been found to be languages on their own now (Nan, Dong, Bei and Zhong)
Xiamen (Amoy) and Taiwan (Taiyu) Minnan dialects are very similar. The Chaozhou dialect is what is known as Teochew, and is a Minnan dialect.
Hokkien is often used to refer to other dialects, I've seen Taiwanese Hokkien, Amoy Hokkien, Teochew Hokkien, and Chaozhou Hokkien used as words for these dialects.