Obama is one of the only first ladies to go sleeveless -- Nancy Reagan is the only other to have done so since Mamie Eisenhower. So Obama is a trend setter even among this tiny group of women. Her shoes are designed by Jimmy Choo, and her diamond jewelry was made by Kimberly McDonald. (Photo at right via Associated Press.) Here's how Obama's dress compares to inaugural gowns past:
(Update, Tuesday: What She's Wearing Today — and Why It Matters)
2009: Michelle Obama, and her famously toned arms, wore a one-shouldered white dress, which was designed by Jason Wu, and peep-toe white pumps.
2005: Laura Bush wore light blue, long sleeves, and sparkly stuff.
The Bushes' daughters were old enough to wear gowns for us to obsess over. They went sleeveless.
2001: Laura Bush wore a red long-sleeved gown. That year, Bush's daughters were still in the prom zone.
1997: Hillary Clinton in glittery gold sleeves.
1993: Clinton wore a lacy blue dress for her husband's first inauguration.
1989: Barbara Bush donating her dress to the Smithsonian a few days after the balls. Notice those pouffy sleeves.
1985: Nancy Reagan's favorite color was red, but she wore white at the start of both her husband's terms.
1981: Nancy and Ronald Reagan.
Here's the back, from the Smithsonian's National Museum of American History. The museum has a huge collection of first ladies' dresses.
1977: Rosalynn Carter chose to wear the same gown she wore to Jimmy Carter's 1971 inauguration as governor of Georgia.
The Smithsonian reports this was a controversial choice. Here's the dress in color:
1969: Pat Nixon reportedly took her husband to pick out her dress. It was yellow, his favorite color.
See it in full color at the Smithsonian's National Museum of American History:
1965: Lyndon Johnson and a fur-trimmed Lady Bird.
The Smithsonian says Johnson intentionally picked a simple dress because she knew it'd go in the museum. She wanted it to age well.
1961: Jackie Kennedy keeps her dress out of the snow, with JFK behind her.
1957: President Dwight Eisenhower and Mamie Eisenhower.
The first couple with son John Eisenhower and daughter-in-law Barbara Eisenhower.
(All photos via Associated Press unless otherwise noted.)