At exactly 12:01 a.m. ET Saturday, on a first-come, first-served basis, the vast social networking site gave users the green light to claim variations of their names or other nicknames of their choosing.
Within three minutes, 200,000 usernames were registered, according to the social media blog Mashable, which covered the registration process live from Facebook's headquarters Friday night.
About 1 million personalized Web addresses had been claimed after an hour. And, through Sunday, Facebook said it had assigned about 5.75 million user names.
Late into the night, Twitter pages, Facebook walls and personal blogs broadcasted messages of celebration and disappointment, as Facebook users either locked-in their names of choice or lost out to others with the same names.
Stuart Miles, 33, editor of the gadget blog Pocket-Lint.com, who lives in Hoboken, N.J., was one of the unlikely ones.
Miles said he hopped on to his computer at midnight but failed to snag his name in time. "I wasn't successful," he said. "I just couldn't get on to the site and someone else got it."
That someone else appears to be another Stuart Miles in Australia. "He was just quicker off the mark than I was," Miles said. "It would have been nice to have but it's not the end of the world."
As he is originally from the U.K., he ended up claiming "StuartMilesUK" instead.
"We're planning to offer Facebook usernames to make it easier for people to find and connect with you," Facebook designer Blaise DiPersia wrote on the company's blog. "When your friends, family members or co-workers visit your profile or Pages on Facebook, they will be able to enter your username as part of the URL in their browser. This way people will have an easy-to-remember way to find you."
Although it didn't know what the participation level would be, the company said it had prepared for a spike in activity and had done quite a bit of testing. It said the registration process over the weekend went smoothly.
"It's rewarding to see the level of excitement about getting a Facebook username," said Larry Yu, a spokesman for Facebook. "It goes to show just how connected Facebook has become to people's sense of identity."
Some personalities and businesses, such as President Barack Obama and General Electric, have had personalized Facebook URLs for a while. But this change makes everyone with a personalized Web address more searchable on Google and Facebook.
Although an impressive number of Facebook users rushed to claim their URLs during the weekend, given that active Facebook users total about 200 million, the social networking site still has a ways to go.
Still, Adam Ostrow, an editor at the popular social media blog Mashable, thinks that in time more Facebook users will customize their pages.
To Prevent Squatting, Users Can't Change or Transfer Chosen URLs
"I think users of other sites are certainly used to having one and Facebook is promoting the fact that they're going to enable this," he said.
While people accustomed to MySpace and Twitter might not have spent their Friday nights camped out at their computers, as they see their friends migrating to personalized pages, they'll likely follow suit, he said.
And if you plan to customize your site, give your user name some thought. Designer DiPersia's blog post cautions users to think carefully about the names they choose because once it has been selected, it can't be changed or transferred.
Even if you misspell the username of your choice, Facebook won't change it. Also, once an account is removed from the site, the user name will not be made available to others for security reasons, the company's Web site says.
Although users can claim personalized Facebook pages without any charge, Ostrow of Mashable speculates that the company may be able to profit off vanity URLs in the future.
Noting that the company has said that generic words like "pizza" and "flowers" will not be up for grabs Saturday, Ostrow said Facebook could potentially sell those URLs for a decent price. "Sports," for example, could be sold to ESPN, he said.
"It's certainly something Facebook is keeping open," he said.