Personally, I don't think Minereum has any value.

You can take a look at Minereum's source code, itself:
https://etherscan.io/address/0x1a95b271b0535d15fa49932daba31ba612b52946#code

Minereum arbitrary created 3200000000000 tokens (for each of their genesis address) on line 27, and will "mine" 32000 tokens every Ethereum block until Ethereum block number 3597381; their mathematical formula for creating new tokens is just addition.

Minereum does talk about using their tokens to help other people create ERC-20 tokens on Ethereum, but.. why can't people just follow Ethereum's guide on ERC-20 tokens?   https://www.ethereum.org/token