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I don't think Nintendo will fragment the userbase for many years so any later tech probably until 2020 will be utilised purely to improve battery life, dimensions etc without affecting core compatibility. However I guess with an improved 1080p screen a newer revision could offer docked performance on the move and eliminate the original portable performance level possibly.
In fact I think this will probably be how this is worked out. First a Switch mini that can only operate in the two portable performance modes of 157 and 200 gflops and later a higher performance Switch that can mainly operates at full docked performance because it has a 1080p screen built in. I just can't see it doing any different than that because it will fragment the market but lets face it docked performance on the move will be a good upgrade anyway.
