It doesn't look like there's any information about the consensus mechanism, until that's described in detail, it's unclear what the advantages are, or if it really is suited to payments. There are existing algorithms (like Avalanche L1, or some of the Ethereum L2s), which have fast finality particularly suited to the point-of-sale use case.

They cut out a lot of work for themselves expecting stable coins to materialize on their own chain. It's Stripe, so maybe they are allowed to mint their own USD stable coin, but that's one coin. They might have been better off making an L2 on Ethereum. Otherwise they are going to have to run Uniswap in their EVM implementation and hope that liquidity shows up.

I can see Stripe's customers wanting to use a solution that just works and is backed by Stripe's own distributed ledger, but I can't see their customers' customers wanting to do the same. Their customers' customers are going to want liquidity to other tokens, and privacy. At this point I don't think that a payments protocol can succeed unless it provides privacy comparable to Monero, liquidity to a major L1 and its family of tokens, and of course, fast finality.

They cut out a lot of work for themselves expecting stable coins to materialize on their own chain.

I assume there will be bridges to other chains so even if, say, USDT is not natively issued on Tempo you can bridge it.

It's Stripe, so maybe they are allowed to mint their own USD stable coin

Stripe has USDB. https://www.bridge.xyz/news/usdb