The Dawn of Decentralized Social Media: An Exploration of Bluesky's Public Opening

TL;DR

Bluesky’s public opening creates a rapid, large-scale shift in user activity within a decentralized AT-protocol-based platform. The study leverages the public Firehose to track 114M activities over 56 days, labeling news sources with NewsGuard and assessing political leaning, credibility, and toxicity, while analyzing language shifts and follower-network changes. Key findings include a heavy-tailed original-content distribution with $P(x) \sim x^{-\alpha}$, a surge in English and especially Japanese content, low overall toxicity, and some suspicious/spam-like behavior that moderation is addressing. The results offer insights into how decentralized platforms manage growth, content quality, and cross-cultural engagement, with implications for news dissemination and platform moderation strategies; limitations include the short observation window and partial labeling of sources, suggesting avenues for longer-term, multilingual studies.

Abstract

Bluesky is a Twitter-like decentralized social media platform that has recently grown in popularity. After an invite-only period, it opened to the public worldwide on February 6th, 2024. In this paper, we provide a longitudinal analysis of user activity in the two months around the opening, studying changes in the general characteristics of the platform due to the rapid growth of the user base. We observe a broad distribution of activity similar to more established platforms, but a higher volume of original than reshared content, and very low toxicity. After opening to the public, Bluesky experienced a large surge in new users and activity, especially posting English and Japanese content. In particular, several accounts entered the discussion with suspicious behavior, like following many accounts and sharing content from low-credibility news outlets. Some of these have already been classified as spam or suspended, suggesting effective moderation.

Figures (15)

• Figure 1: Complementary cumulative distribution of user activity (number of original posts) on Bluesky during one day (March 4, 2024). The dashed line is a power-law fit of the distribution, which yields a slope of 1.53 ($x_{min}=1, x_{max}=1{,}000$).
• Figure 2: User activity on Bluesky before and after the opening. The vertical dashed line represents the date of the opening (Feb 6).
• Figure 3: Sharing activity on Bluesky before and after the opening. The vertical dashed line represents the date of the opening.
• Figure 4: Top 10 languages in Bluesky. Bars of the same color sum to one.
• Figure 5: Trend of 5 top languages on Bluesky during the observation period.