Maybe something like:
Ethereum Stack Exchange is a question and answer site for users of
Ethereum, the smart contract enabled blockchain network. Technical
questions about Ethereum are welcomed here. With your help, we're
working together to build a library of detailed answers to every
question about Ethereum.
Seems this could be a community wiki and combining the OP and Hudson's answer:
Ethereum Stack Exchange is a question and answer site for users of Ethereum, the smart contract enabled blockchain based consensus network. It's built and run by you as part of the Stack Exchange network of Q&A sites. With your help, we're working together to build a ...
There are a lot of great options, but I have to vote for How can a contract run itself at a later time?. For one, I think it is a short question that most Ethereum newbies would understand and be curious about. Moreover, while the top answer is long, it is an excellent response. Additionally, you can easily find answers to a lot of the other questions by ...