https://news.xbox.com/en-us/2018/03/28/community-thank-you-sea-of-thieves/
Worth noting MS considers things like Quantum Break first party even though it isn't by a first party studio. It'll also be interesting to see how Gamepass has contributed to the overall player count.
They also said this:
The worldwide excitement for Sea of Thieves has made it the fastest-selling first-party new IP of this generation. Having witnessed more than a million players on launch day, our community continues to grow and now has more than two million players. Alongside this, Sea of Thieves is already the best-selling Microsoft Studios first-party title on Windows 10.
Worth noting MS considers things like Quantum Break first party even though it isn't by a first party studio. It'll also be interesting to see how Gamepass has contributed to the overall player count.
More than 100,000 players have streamed Sea of Thieves since launch, resulting in more than 10 million hours watched in the last week. Thank you to all the content creators and community who have streamed Sea of Thieves and entertained viewers with their creativity and sense of fun as it jumped into the number one slot on Twitch and Mixer several times this past week.
More than half of a million new Xbox Live friendships have been forged to date and over 400,000 players have joined an Xbox Club to find pirates to share stories with.
They also said this:
We know the response has led to some scale challenges and exposed some bugs we have addressed and will continue to address. Please know that the team at Rare is working hard to tackle any player-impacting issues and this is our number one priority.