Besides some additional revenue (which may in fact be offset from lost revenue due to worse bowl selections) a conference championship game is a terrible idea for the conference. Even if the B10 expands, I would still prefer that there was no conference title game. In not one season this decade would a conference title game have helped a B10 reach the title game.
2001: Only season in which a conference title game could have improved the B10 champs standing. Illinois won the B10 with a 10-1 record and finished 8th in the BCS standings. While they could have moved with with another win in a conference title game, no way do they move form 8 to 2.
2002: Our championship season. All a conference title game does is either eliminate OSU from the title game or perhaps make Iowa lose their BCS bowl berth with an additional loss. Nothing to gain everything to lose this year.
2003: No help here either. Conference title game would have been a rematch of OSU/SCUM with the loser likely losing their BCS bowl berth. Two loss SCUM was ranked 4th in the BCS, but had no hopes of moving up with another win over OSU, as the top 3 (LSU, OU, USC) all only had 1 loss. Again, nothing to gain, everything to lose.
2004: Iowa and Michigan tie for the B10 title, both with 2 losses and finish 12th and 13th in the BCS standings. Conference title game clearly does not propel either of these teams past undefeated USC, OU or Auburn into the title game. No additional BCS game for the B10 this year, so only a slight rankings +/- to the winner/loser. Iowa and SCUM didn't play each other during the season, so I guess this would have been a nicer way to determine the Rose Bowl berth.
2005: OSU and PSU tie for the B10 title and finish 3/4 in the BCS standings. A victory by either over the other in a conference title game is of no help - USC and Texas were undefeated. A conference title loss drops OSU out of a BCS bowl most likely. Also, if Texas loses in the B12 title game, PSU has a shot at the title game. A loss in a B10 title game to OSU, however, would have left Texas clearly in the BCS title game if such a scenario had occured. Again, no potential gain, all potential negative.
2006: OSU/UF BCS title game. SCUM finishes 3rd. Though perhaps preposterous, I guess it is possible a B10 title game COULD have helped this year. OSU wins The Game. Then SCUM wins the title game rematch. Potentially, the BCS title game could have been OSU/SCUM part 3 to settle things once and for all. Most likely, all a conference title game does is make The Game meaningless here and just shuffle bowl assignments (BCS Title/ROSE) between the two teams. No chance of the B10 losing a BCS berth either, as UW would have taken the spot had UM lost to OSU again. So I guess this year has to be considered a positive for a title game, but what a wacky scenario.
2007: OSU/LSU BCS title game. B10 conference title game again would have been an OSU/SCUM rematch. Clearly this game would be of no help. A loss drops OSU out of the title game and a win would not put SCUM anywhere near the title game. OSU may not get a BCS game with a loss to SCUM either. Again, all negative.
2008: Conference title game would have been an OSU/PSU rematch. Helps BCS #8 PSU or #10 OSU move up, but definitely not to #2. OSU definitely loses the BCS berth with a loss and PSU perhaps with a loss. No benefit at all.
2009: Would have been and OSU/Iowa rematch. A win clearly does not propel either team past Bama/Texas/UC/TCU/Boise/UF. Loser is probably out of the BCS, but PSU likely takes their place. No real loss, but no gain.
So from 2001 to 2009 the only time a conference title game could have helped a B10 reach the title game and not hurt its chances was in 2001 where Illinois would have needed to jump from #8 to #2 (to be fair, they only had one loss, as did actual #2 Nebraska, but they had no chance to move up that far in reality) and in 2006 through an odd scenario where OSU and SCUM potentially meet 3 weeks in a row.
Otherwise, all such a game does is either cost B10 teams BCS title shots or BCS bowl berths. I don't see why the conference would want to add such a game.
(I typed this up quickly, I apologize for any bad grammar)