According to the UK's domain name registry, Nominet, the first person to switch from .com to .uk is British icon and tech enthusiast Stephen Fry. Well, he does own five smart phones, for goodness' sake.
Nominet is also rolling out what it claims to be 'the world's largest welcome sign' (pictured), on the approach to Heathrow Airport. Weather-permitting, it's visible from 35,000 feet, so plenty of travellers should see it.
Is .uk a good idea?
But amidst these celebrations, what does .uk mean for businesses in the UK? For that matter, what does it mean for UK internet users as a whole?
Well, Nominet argues that .uk domains are 'more succinct' and comparable with the likes of .de (Germany) and .fr (France).
According to its research, when presented with a series of new domains, such as .company or .london, sites ending in .uk remain the first choice for 93% of British users.
But since proposals for .uk were first floated, they've come in for a fair bit of criticism.
Detractors say businesses with existing .co.uk domains will face increased costs, because they'll feel obliged to register the equivalent .uk domain too.
And could having both .co.uk and .uk domains increase consumer confusion?
Eleanor Bradley, chief operating officer of Nominet, reckons .uk is a no-brainer for such a digitally literate population: "The new .uk is for people who want a short, memorable domain with the popular and trusted .uk ending. We know this combination appeals to our tech-savvy, digitally-engaged population."
Your .uk domain is reserved
If your business owns an existing .co.uk domain name, you get first refusal on the equivalent .uk domain. You can exercise this right at any time in the next five years.
Nominet will be contacting these businesses to ensure they're aware of this opportunity.
This means if you own yourwebsite.co.uk, nobody else can register yourwebsite.uk until after 10 June 2019. So if you're unconvinced about the prospects of .uk, you can wait a few years before deciding whether to register it.
On the other hand, if you like to embrace new things and you're in the market for a domain name, you can register .uk domains from 8am this morning.
The first sites using .uk — including stephenfry.uk — should go live during the day.
Difficult domain name choices
In many ways, .uk seems like a very British domain name launch. While truly different domain names like .beer, .investments, .cash and even .rip have been grabbing the headlines, we've launched one that's a whole three characters different to .co.uk.
Will that be enough to catch on alongside established standards like .co.uk and .com, and against a background of more adventurous alternatives?
Only time will tell. But if they've managed to get Stephen Fry onside, this new domain has got to be in with a chance.