For the folks that love to Steem and hate being down palnet.io is currently running off of the minnowsupport node and is currently operational.
Hardfork 22 should start working again shortly. There was an edgecase bug that stopped the chain from handing ~2T steem to an account (who didn't do anything wrong, just bugged math). Chain did exactly what it was supposed to do and stopped the transaction from going through, a fix was determined, implemented by witnesses, chain was forced to replay which took most witnesses 4-6 hours.
In some cases where a pre HF21 file was saved witnesses and RPC nodes were able to start back up faster and not have to replay the whole thing. That's how the minnowsupport node came online quickly. Thanks @drakos for being smart and diligent!
Anyway, this fun little stoppage should be done as soon as Steemit RPC nodes finish replaying, but until then feel free to enjoy palnet.io