Churches chartered 70% of the units in 2012. The top 6 denominations which charter BSA units and how they will react to the vote ...
1. LDS - They adopted BSA as their official male youth program in 1913. The church threatened to leave BSA in 2000 if BSA submitted to the homosexualists. The church leadership announced in APR 2013 that it was satisfied with the BSA resolution to accept open homosexual youth. Mitt Romney wants all, adults too, homosexuals to be eligible to be in BSA. The LDS Church is most worried about their missionary programs being negatively affected by anti-homosexual publicity. The LDS will continue in the BSA.
2. UMC - They are a house divided over homosexuality. Look for a schism in this denomination in the coming years. Its male youth committee, United Methodist Men, essentially sat this issue out and was non-commital. Most churches will continue to charter BSA units.
3. RCC - Their National Committee on Catholic Scouting took a pass on this issue. They cited church doctrine about homosexuality but essentially said they would go along with BSA's decision. Very, very sad given this denominations 25+ year homosexual predator priest scandal.
4. Lutheran - BSA does a disservice by grouping all the different Lutheran sects under this heading. The largest, ELCA, was essentially quiet on the issue, but it does ordain homosexuals. The LC-MS came out strongly against the BSA resolution. ELCA will stay in BSA but LC-MS may well bow out.
5. Presbyterian - Same thing as Lutheran - way too many different flavors of Presbyterian sects. The largest, PC-USA, ordains homosexuals. It was essentially quiet about the issue but will most likely remain in BSA. The much smaller PCA could very well leave BSA.
6. Baptist - Same as the Lutherans and Presbyterians - way too many flavors. The elephant in the Baptist living room is the Southern Baptist Convention. Its leadership will officially condemn BSA and recommend its autonomous congregations to leave BSA and support its own male youth program, the RA's - Royal Ambassadors.
Why would the Mormons leave? They supported and demanded this.