Here are some things to consider if you're hoping to have a "Boardwalk Empire" wedding:
Alcohol...or Not
Liquor is often a sensitive subject during wedding planning, but the "Boardwalk Empire" theme provides a reason to have no alcohol, some alcohol or an all out bash. If you're opting for a dry wedding for personal or financial reasons, you can use the prohibition era as a lighthearted reason. The availability of beer only (or a simple champagne toast) could also be explained with this reason. An all-out bash with an open bar would also fit in well for a "Boardwalk Empire" theme--just pretend you're at Babette's with Nucky!
Inspired Photography
It isn't always easy for a couple to convey their wedding photo vision to a wedding photographer or videographer, but most creative types will be full of ideas at mention of a "Boardwalk Empire" theme. Photographs can include beach photos, boardwalk pictures and a few portraits as they would have been done in that era.
Fashion Forward
Fashion from the 1920s is making a comeback in era-inspired clothing in department stores. Whether you'd like a traditional long-sleeved wedding gown or a savvy flapper dress, your gown will fit in with the theme. Especially slender, less-busty brides may have particular luck looking the part considering the fashions of the day.
Wedding Venues and Landscape
While Atlantic City still retains a similar spirit to its 1920s self, many of the hotels and venues that existed during that time were demolished when Atlantic City legalized gambling in the 1970s (to make room for large casinos). Due to fires and storm damage, the boardwalk itself is not the same as the original, though still evokes the same feelings. Many gambling establishments and restaurants are providing a prohibition-era feel thanks to the success of "Boardwalk Empire," so shop around.
Other popular wedding themes are often inspired by earlier times, but a 1920s wedding allows for plenty of readily-available information. If you live locally, the Atlantic City Public Library and their Nucky’s Empire: The Prohibition Years exhibition may be of particular use.