http://www.dota2.com/international/format
This is completely unfair to people that are traveling great distances and at great cost to see their favorite teams and players play, only to find out that they will never even make it to the Arena.
There was nothing wrong with the previous format. I realize the round-robin 16 team format might have been done to prevent any imbalance in the group stage, but this is not a good solution. If the change was made in the interest of time, it is still not a good solution. The BO1s of the lower bracket had plenty of upsets, but at least people got to see their favorite teams on stage.