This week, Bitcoin and other cryptocurrencies are poised for significant developments, particularly with the Federal Reserve's anticipated interest rate decision on December 18. Fantom is set to launch its Sonic L1 mainnet, promising enhanced transaction speeds and reduced costs, while Avalanche's major upgrade, Avalanche9000, goes live today, transforming its subnet functionality. Stacks will introduce sBTC on December 17, facilitating Bitcoin's integration into DeFi, and LayerZero will hold a governance vote on December 20 regarding a fee switch for cross-chain messages, potentially impacting token economics.