If there were no expanded playoffs this year, at this point of the season you would have a good idea of the 4 teams that are probably going to make the 4 team playoff and realistically it would be about 8 or 9 teams right now that have a chance.

This season with 12 teams and conference champ auto bids for top 5 ranked conference champs, you still have a ton of teams that could still make it. 1 loss doesn't eliminate you, maybe even 2.
I think this creates much more interest for games across the country. many more games will have an impact on who makes the playoffs, going deep into the season.
It seemed in previous years that we were only talking about a half dozen teams at this time of the year. Now ESPN has 24 teams that have at least a 13% chance of making the playoffs.

Lots of games with real meaning now.

Makes for a fun season.