By Jessica Ravitz, CNN

Big news broke in the Mormon world this weekend, when the president of The Church of Jesus Christ of Latter-day Saints announced a lowered minimum age requirement for missionary service, most notably for women.

Women can now go out in the field to serve their church at 19, instead of 21. Though this may not seem monumental to outsiders, some Mormons say it's a game-changing moment that may rewrite women's futures and even influence broader dynamics within the LDS Church community.

“The narrative of young women has been that marriage trumps everything else as your most important spiritual pursuit,” explained Joanna Brooks, scholar, blogger and author of “The Book of Mormon Girl: Stories from an American Faith.” This shift “signals a reorganizing of expectations for women’s lives. … It changes the storyline.”

By 21, many Mormon women are either too deep in their search for a husband, if not already married, or too entrenched in their education or career path to step away for a Mormon mission, Brooks said. With the lowered age requirement, they have more choice. They, too, can go out in the world, study their faith intensely, follow spiritual callings and grow as individuals before they marry. And, Brooks said, they can be viewed more as equals when they return and start dating.

The surprise announcement by President Thomas S. Monson, who’s considered a "prophet, seer and revelator" by Latter-day Saints, left Brooks in tears. She wasn't alone. The Universe student newspaper at Brigham Young University reported that dorm halls "filled with shrieks, tears and disbelief." The announcement was made Saturday morning at the semiannual LDS Church General Conference, as more than 20,000 gathered in a Salt Lake City conference center to hear from church leadership. Millions of other Mormons tuned in via satellite, the Internet and television.

Not since the 1978 announcement that black men were able to serve in the priesthood has a revelation been greeted with such excitement, Brooks suggested in a blog post. That sentiment was echoed in the BYU newspaper, where an 18-year-old student drew the same parallel to '78: “It feels like one of those days. There are so many opportunities for so many more people now.”

There are 58,000 Mormon missionaries currently proselytizing in the field, of whom generally about 15% are young women, a church spokesman said. There are also older couples serving in these ranks, but the vast majority of missionaries are young men. Previously able to start service at 19, men can now answer a call to serve at 18 - giving them the option to head out right after high school, a move that The Salt Lake Tribune reported would affect admissions, scholarships and recruiting at Utah colleges. But that decision, too, is a shift that church officials hope will increase missionary numbers.

“We affirm that missionary work is a priesthood duty – and we encourage all young men who are worthy and who are physically able and mentally capable, to respond to the call to serve,” Monson told Latter-day Saints on Saturday. “Many young women also serve, but they are not under the same mandate to serve as are the young men. We assure the young sisters of the church, however, that they make a valuable contribution as missionaries, and we welcome their service.”

The expectation of women to serve may not be the same, as they do not hold the priesthood. And their missions, if they do serve, are still limited to 18 months, while men serve for two years.

It's details like that that dampen enthusiasm about the age change among some Mormon women.

"We were told today that it's a vital time for the Lord's work and we need all hands on deck. Why are some hands valued more?" wrote Jana Riess, a prolific Mormon blogger and author of, among other books, "Mormonism for Dummies" and "Flunking Sainthood: A Year of Breaking the Sabbath, Forgetting to Pray, and Still Loving my Neighbor."

"It's progress for women. It's just not equality," said Riess, who initially shared in the tears of joy. "And after a few glorious moments of believing it would be, that stings."

But providing more equity in opportunity, in a church where change happens slowly, is the big takeaway, said Brooks, a feminist and activist who, as a college student and beyond, faced her own struggles to find her place in the only church she’d ever known.

“I would have relished the chance to get out early and put my faith to work,” she said. “Subtle changes can produce wide effects.”