Ethereum's experimental consensus specifications now include an implementation draft for EIP-8198, known as Quick Slots. The proposal replaces the assumption that every slot lasts 12 seconds with a schedule that can change at a fork boundary. Consensus specification, EIP-8198.
The current consensus draft describes an intended first reduction from 12 seconds to 10 seconds. It also says the activation epoch and accompanying blob settings have not been scheduled. The public EIP page still contains an 8-second parameter table, which shows that the design is still moving and should not be presented as an agreed mainnet setting.
Changing the slot length affects more than how quickly a block appears. Issuance, validator churn, inactivity penalties and intra-slot deadlines are tied to elapsed time. The draft introduces a historical duration schedule and rescales several consensus calculations so that their wall-clock behavior remains comparable after a change.
Shorter slots reduce the time available for block propagation, validation and attestation aggregation. The proposal therefore calls for performance testing before committing to a final duration. Applications and monitoring tools that assume a constant 12-second slot would also need to read the active schedule across a fork boundary.
This is specification work, not a mainnet launch. EIP-8198 remains a draft, the feature documentation labels itself work in progress and Ethereum's published mainnet configuration does not schedule the change.