This happened 3 hours ago. Binance powered up almost 32 million Steem - probably of user funds, I doubt they own that much - and set dev365 as their witness vote proxy.

Dev365 is an account controlled by Justin Sun, that voted for 20 witnesses and changed the Steem version to 0.22.5. Apparently this unlocked the soft-locked stake of Steemit Inc (also owned by Sun), which was then also used to vote those witnesses. This is the code for the update. This is a hostile takeover and I advise anyone to stay away from exchanges that use the user funds to vote witnesses on blockchains.