Is Filecoin working with Chainlink (LINK) as it relates to Smart Contracts?
Not directly right now AFAIK. There are two ways I see the system interfacing with a service like Chainlink in the future.
(1) once filecoin supports user defined smart contracts we will want to provide oracle services for these contracts. Note that user defined smart contracts are not planned until well after mainnet so this is still very far out. Our builtin smart contracts (actors) are not using any oracles.
(2) as a source of verifiably stored data it would be interesting to use the filecoin network as a way to provide oracle data to a service like chain link. This likely requires more thought and design around incentivizing data retrieval and is also out of scope of our immediate path to mainnet launch.