A new rival stablecoin has been launched, backed by companies including Visa, Stripe, Coinbase, and BlackRock, which is seen as a threat to Circle's USDC stablecoin. The launch has led to a decline in Circle's stock price, but some analysts believe the sell-off is overdone and see potential for Circle's stock to rebound. The impact of the new stablecoin on Circle and the broader digital currency market is uncertain, with varying opinions on the outcome.