Doing the math...

[BostonOrange]

...let's say the Big 4 conferences all go to 16. The following 50 teams are currently in:

ACC:
Syracuse
Pitt
BC
Maryland
VT
Virginia
UNC
Wake
Duke
Clemson
NC St
GTech
FSU
Miami

Big 10:
PSU
Nebraska
Michigan
MSU
Ohio St
Iowa
Wisc
Minn
Indiana
Northwestern
Illinois
Purdue

SEC:
Florida
Georgia
South Carolina
Auburn
Bama
LSU
Arkansas
Tenn
Ole Miss
Miss St
KY
Vandy

Pac 12:
Washington
WSU
Oregon
OSU
Cal
UCLA
ASU
Zona
Colorado
Utah
USC
Stanford

That leaves 14 slots for the following teams (in very rough order of clout)
1. ND
2. TX
3. Oklahoma
4. A&M (almost done to SEC)
5. Uconn
6. Ok St
7. Mizzou
8. Kansas
9. WVU
10. Kansas St
12. Rutgers
13. Louisville
14. TCU
15. Iowa St
16. TCU
17. Texas Tech (package deal with UT?)
18. Baylor
19. Boise St
20. BYU
21. Cincy
22. USF
23. UCF

So...9 teams on that list are going to end up either totally out of the BCS or in some weird mismatch 5th conference. I think anyone out of the top 4 has to be nervous...

 

[Moontan]

TCU twice?

 

[Chip]

So when you remove 1 TCU, and then figure 3 of those teams are already not included in the BCS without meeting a minimum requirement, it's 5 teams who would have to worry.

But I also think 4 X 16 isn't every going to happen. Congress will get involved (yeah I know, better things to do, and no direct power here). They'll scare enough people to make it more inclusive.