Markets put bsky exceeding twitter at 44%, 4x higher than mastodon.
My P would be around 80%. I don't think most people (who use social media much in the first place) are proud to be on twitter. The algorithm has been horrific for a while and bsky at least offers algorithmic choice (but only one feed right now is a sophisticated algorithm, and though that algorithm isn't impressive, it at least isn't repellent)
For me, I decided I had to move over (@makoConstruct) when twitter blocked links to rival systems, which included substack. They seem to have made the algorithm demote any tweet with links, which makes it basically useless as a news curation/discovery system.
I also tentatively endorse the underlying protocol. Due to its use of content-addressed datastructures, an atproto server is usually much lighter to run than an activitypub server, it makes nomadic identity/personal data host transfer much easier to implement, and it makes it much more likely that atproto is going to dovetail cleanly with verifiable computing, upon which much more consequential social technologies than microblogging could be built.
The algorithm has been horrific for a while
After Musk took over, they implemented a mode which doesn't use an algorithm on the timeline at all. It's the "following" tab.
For a while I just stuck to that, but eventually it occurred to me that the rules of following mode favor whoever tweets the most, which is a similar social problem as when meetups end up favoring whoever talks the loudest and interrupts the most, and so I came to really prefer bsky's "Quiet Posters" mode.
Recently a bunch of my friends, primarily in the contra dance world, have decided to give Bluesky a try. I think a lot of this is a post-election reaction to Musk and X (Twitter), but since I'm not on Twitter I'm mostly seeing the Facebook side. Regardless, I'm happy to see energy for migration: I'm pretty unhappy with FB [1] and if we can get critical mass on a better platform that seems good.
Playing with Bluesky it seems fine. I turned off Reposts (Settings > Following Feed Preference > Show Reposts) because otherwise my feed was full of things from people I don't know that I wasn't interested in. I like that it seems to be run by people who value openness. Not sure yet whether it's default algorithm is any good, but I like that I can experiment with other algorithms or (if I'm willing to put in a bunch of work) I could write my own.
If I end up liking it I'll write a comment bot like I did for Mastodon. Speaking of which, I'm still cross-posting there [2], from a previous effort to move to a more open platform, and I'm still reading it with with Shrubgrazer. But more friends have joined Bluesky in the past few days than ever joined Mastodon, so this seems more likely to take off.
If you'd like to add me I'm @jeffkaufman.bsky.social.
[1] Very high ad load, keeps trying to push reels and groups, increasingly buggy (for months long comment threads only load if I switch each one from the default of "most relevant" to "all comments"), doesn't show me posts from most of my friends, still quite bad at predicting which of my friends to show my posts to, broke my comment bot enough times that I've given up on it, doesn't support good search because people find it creepy, terrible flow for review if one of my posts is accidentally removed, etc.
[2] As platforms proliferate I'm glad to be using a POSSE ("Publish (on your) Own Site, Syndicate Elsewhere") strategy.