He wore a single-vent, notch-collar tuxedo with a white bow tie and an American flag pinned to its lapel.
The gown's slight train swirled pleasingly and the new first lady's shoulder-sweeping earrings picked up the gown's sparkle.
It caused a stir on the Web, as devoted fans debated whether it best suited Obama's figure - and their high expectations.
Regardless, the gown will be donated to the Smithsonian, according to tradition, the first lady's spokeswoman said. Surely it will be noted that fellow first ladies Jackie Kennedy and Nancy Reagan also wore white inaugural gowns.
The fashion industry has anxiously looked to the election of Obama for months, embracing his wife as an ambassador, along the lines of Kennedy.
Long loved for her willingness to confidently mix high and mass fashion, Michelle Obama didn't disappoint in accessorizing her day look: green gloves by J. Crew and green patent leather pumps by Jimmy Choo.
"What's so powerful about Michelle Obama is we all see ourselves in her," said red-carpet and magazine stylist Mary Alice Stephenson. "She's a modern woman who is fashionable and even flamboyant in her style and she is still taken seriously."
Toledo, too, said she wanted her outfit to convey optimism.
"I didn't want a traditional blue or red," Toledo said. "That color has sunshine in it. I fell in love with it. So did she."
Whether or not everyone loved the looks, that message clearly came through.