I have Pokemon all the way back from Emerald. That would be like 8 or so years of my life wasted raising and training them. I would be absolutely furious if they didn't include a way for me to transfer my Pokemon over. I would probably quit Pokemon if that happens.
Yeah, you and me both... If migration was excluded in the third generation, I would consider skipping the games altogether. What would have been the point of me training all of my Pokemon in the past games? If I can't keep them, I wouldn't want to play another game in the series.