TL;DR At launch $ETH will be used at the protocol level for transaction fees and bond from validators, while $LINK will be used at the app level to pay for oracle services such as Price Feeds, verifiable randomness, & L2->L1 messages
2/ An important note: Ethereum (settlement layer), Chainlink (oracles), and Arbitrum (L2 rollup) are entirely complementary technologies, each is an important piece of the puzzle that will allow for the growth of the #DeFi ecosystem at scale
Each component is needed
3/ Starting with Arbitrum's current developer documentation
$ETH will be the medium of exchange that users pay for transactions fees and is the currency staked by validators who post fraud proofs
"@connexun is pleased to announce that it will be making premium news data accessible to blockchain applications called smart contracts by launching its own #Chainlink node"
"@Barn_Bridge is initially sponsoring the $BOND/ETH Price Feed on #Ethereum, while the $BOND/USD Price Feed has launched on @0xPolygon. This represents the first step in a long-term integration with the #Chainlink Network"
"@CryptoOptyn uses #Chainlink to price options contracts and synthetic assets, which is important for minting new positions, swapping contracts/assets, settling contracts at expiry, calculating health factors, and managing the liquidation mechanism"
The @bsnbase framework allows Chinese 🇨🇳 and global institutions 🌐 to seamlessly spin up a blockchain node and interface with cross-chain and data-driven #Chainlinked Smart Contracts
"We are proud to announce that we’ve updated the Chainlink Market, allowing users to discover and consume services from leading data provider operated @Chainlink nodes"
"The @curio_invest Stablecoin $CSC uses #Chainlink oracle Data Feeds to access a benchmark price on each of the underlying cars backing CTn tokens, ensuring the issuance of fair market loans & full collateralization of CSC"
"@curio_invest is pleased to share that it is now leveraging #Chainlink Oracles live on #Ethereum and eventually #Polkadot to obtain valuations for CTn tokens, starting with price benchmarks for the Ferrari F12tdf and then moving to other collectible cars"
"The combination of @AugurProject, @chainlink, and @0xPolygon offers full stack infrastructure for supporting secure, low-cost betting markets that settle in near real-time and according to premium data sources"
"With #Chainlink integrated, anyone in the world will be able to create their own betting markets on #Augur Turbo for a wide range of different sports events in the NBA, MLB, MMA, and Olympics, with additional support for NFL, college football, soccer, tennis, golf, and e-sports"
"#Chainlink is securely delivering flight data and arrival/landing times from multiple high-quality data sources directly to @OTONOMI3's air cargo insurance smart contracts"