These days, couples are as likely to be wed in a park or museum as in a courtroom or a house of worship. The setting isn't all that has changed. Visibly pregnant bridesmaids and male maids of honor are just a few things that were once frowned upon but are now widely accepted.

Brides and grooms-to-be may face fewer restrictions, but that doesn't make the rules of etiquette any less essential. As anyone who has planned or participated in one quickly learns, weddings are a quagmire of potentially hurt feelings, hard-won compromises and sticky situations.

If your questions are limited to invitation wording, seating arrangements and thank-you cards, you're lucky -- these questions have well-established answers. But what about questions so new that it's not clear that etiquette guidelines have even been established?

When technology changes the way we interact, such as via e-mail or social networking sites such as Facebook, the rules of etiquette have to catch up. While you can poll your acquaintances or post your questions to wedding forums to see what other people think, for definitive answers it's best to go to an expert.

I took my questions to Anna Post, great-great-granddaughter of etiquette maven Emily Post and a modern-day etiquette expert whose books include "Do I Have to Wear White? Emily Post Answers America's Top Wedding Questions" (William Morrow, 2008).

You're so excited about getting engaged you want to shout it from the rooftops, but hold off for just a few minutes. Technological innovations may have made day-to-day communication faster and easier, but when it comes to your wedding, doing it right is more important than doing it quickly.

Before you update your Facebook status, communicate the news of your engagement in a more personal manner to family and close friends. The congratulations might not come quite as quickly with phone calls or visits, but they'll be more meaningful.

Wedding invitations should always be tangible, not virtual, and Ms. Post doesn't expect that to change anytime soon.

"I just don't think a computer screen can have the same importance as a beautiful piece of paper that was addressed just to you," she explained.

E-mail is fine for save-the-date announcements, especially for weddings that aren't ultraformal. But Ms. Post cautions couples to consider sending hard-copy announcements to anyone who might not be Web savvy, and to follow up to ensure that important information doesn't get lost in spam folders.

One additional caveat: The convenience of e-mail save-the-date cards may come back to haunt you. Make sure you have a sense of your wedding budget and overall guest count first. One thing hasn't changed: Anyone who receives a save-the-date notice, whether in the form of an e-mail or an engraved card, must receive an invitation to the wedding.

The etiquette of wedding gift-giving varies greatly among families, regions and cultures. When they first appeared, wedding registries were considered crass and inappropriate. Today close friends and family, eager to get first pick, may start asking where you've registered just days after you announce your engagement.

Some things haven't changed. You should never print registry information anywhere on your invitation. It is, however, fine to put registries on wedding websites, which Ms. Post says are more and more common.

She recommends having no more than three registries and including at least one national brick-and-mortar store for more traditional guests.

While honeymoon registries and other alternative registries are a little more common than they used to be, Ms. Post cautions couples to consider whether they're appropriate choices for their circles.

"The honeymoon registry makes me a little bit uncomfortable," she said, "because it feels a little bit close to asking the people to pay for the wedding itself."

Mortgage- or down payment-themed registries raise similar concerns. "It's always been fine for people just to give cash," Ms. Post pointed out. "What's different now is that people are asking for it."

Wedding etiquette columns and books tend to focus on the responsibilities of the bride and groom. But one of the newest topics of concern has more to do with the behavior of guests after the wedding. Just in the past six months, Ms. Post has started receiving questions about if and when it's appropriate for guests to post wedding pictures and videos on Facebook or other websites.

She suggests asking the couple for permission and letting them preview the photos that include them or their family. Getting permission isn't mandatory, but Ms. Post is absolute about one thing: "Never, ever [post] any photos that would show the bride and groom or the wedding in an unkind or unflattering light."

If friends and family do post pictures that aren't your favorites, remember that they're probably not trying to offend you but, rather, trying to share with others how much fun they had at your wedding.

Doug Oster writes a blog, "Growing With Doug," exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.