It has it's own blockchain that will be merge mined with bitcoin. Likely all miners will adopt it because as always they like to make money. This means it will have the same security as bitcoin or litecoin in this case. It's as likely that it will be "censored" in someway as a 51 percent attack happening to bitcoin. A little far fetched.
Don't forget that Ethereum has already publically "censored" when the blockchain was changed for special interests.
I understand that you have a vested interest in Ethereum; but, to dismiss something with huge potential as a "gimmick" sounds somewhat condescending. The idea that others can't solve problems in ways that Vitalik didn't envision makes him sound somewhat God like. He's smart but, not omniscient. There are other smart folks in this space and they are moving forward.
RSK just received another round of funding at Consensus 2017. Not bad for what you dismiss as a "gimmick".
http://www.coindesk.com/opening-testnet-to-public-rsk-announces-3-5m-funding/