While I believe that for certain applications MT will keep on improving (and will become a useful tool even for many translators), the sky is not falling on our profession. At least not yet:
The verb “Switch”, in “Switch your TV to the corresponding Component Video input to view your XYZ video playback” is translated in opposite ways by Google Translate and by Bing Translator – and both of them are wrong. Google translates “switch” as if it were “switch on”; Bing as if it were “switch off” – when of course the meaning is neither the former nor the latter.
This is just anecdotal evidence, of course, and by itself means little, but it underlines the fact that a machine translation program does not understand the text, and that relying on MT can lead to some disastrous errors.