Yep: as she announced it in a tweet, the Lastminute.com founder Lane Fox - also known as Baroness Lane Fox of Soho - added that the role was the "Best. Job. Ever.".
The appointment was confirmed by Twitter's executive chairman, Omid Kordestani, who added that Hugh Johnson, the vice chairman and chief financial officer of Pepsi, was also joining.
The gravity of the occasion caused Johnston to issue his first Tweet:
Meanwhile, Peters Currie and Chernin will depart when their terms expire.
The entire Board is working to bring greater diversity to our ranks. Watch this space— Omid Kordestani (@omidkordestani) April 8, 2016
And Jack Dorsey, the company's chief executive, also vowed to make the 10-person board - which, with Lane Fox, now includes two women - more diverse.
More additions to the board soon, ones that will bring diversity and represent the strong communities on Twitter. This matters & is a must.— jack (@jack) April 8, 2016
Two weeks after Twitter's 10th birthday, the company isn't in the easiest position. Yesterday shares fell after Mortgan Stanley cut its earnings forecast for the company, saying its "core engagement remains in decline".
“Engagement and new user trends remain troubling,” said analyst Brian Nowak in a note, which estimated that Twitter will add 2.6m global monthly users in 2016 and then 300,000 in 2017 (previous estimates put the 2016 figure at 5.2m and 2017 at 3.4m).