If the Jays didnt trade him Halladay would have left after this coming season in free agency... and the Jays would have got nothing it return.
The Jays got Drabek, who projects as a solid number 2 starter and should be in the majors by next year, D'Arbour, who should be an everyday starting catcher in 2 or 3 years, and Wallace, who could be with the team at the end of this season and projects to be a guy whos going to hit .300 with 20-30homers and 100RBI for years to come.
The Jays got a great return... obviously it sucks to see Doc go, but it was going to happen now or later... and at least now we got some really good prospects in return, rather than nothing.
Any fans who boycott the Jays for this are ignorant fools who know nothing about baseball.