Sites like Islamictube, naseeb.com and muslimsocial.com cater to Muslim communities but religious leaders, particularly those who work with younger generations, use Facebook and other mainstream networks to communicate.
"I think that's a good thing," said Edina Lekovic, communications director for the Muslim Public Affairs Council. "I think that particularly in our community, we experience mosques, in the worst case scenario, that have lost touch. They're trying to do the same old tired Sunday school program."
But, she said, more forward-thinking mosques are creating Facebook pages for youth groups and posting sermons and schedules online.
"In some ways it creates competition in the marketplace," she said. "These days, you don't get off the hook."
But while religious leaders are using new technology to recruit and reach out to members, some have a few reservations.
"I'm of a couple of minds about it," said Rabbi Howard Goldsmith of New York City's Temple Emanuel. "On one hand, in terms of communicating and teaching, I think they're vital tools. On the other hand, people look to authenticity and groundedness that is often elusive in cyberspace."
For him, Facebook is a great way to find people and let them know about temple activities. He'd even try Twitter if he could fit it in between all the rituals such as weddings, funerals and baby-naming services that call for a live rabbi.
But, ultimately, he said, Facebook isn't a substitute for face-time, especially in the Jewish faith, which has such a strong tradition of gathering in person. "There's so much virtual life out there already; people are looking for something real," he said.
As for InformationAgePrayer.com, the new Web site that automates prayer, he said, "I think that prayer is about heightening our awareness about the world around us and continuing to reinforce our relationship with God. And I don't think that having a computer recite our prayers for us accomplishes either of those goals."
James Clement van Pelt, program coordinator for Yale Divinity School's Initiative in Religion, Science and Technology, said churches that embrace the technology have found considerable success. But he and connected members of the clergy believe that even as technology changes the way people express their faith, virtual churches will never replace brick-and-mortar ones.
"People are always looking for guidance," van Pelt said. "When people have questions, they look for sources of guidance. I think that's not going to change."