Short answer, yes. Developers have replicated the fundamental concepts of ERC721; however, there is not some arbitrary numbered schema that everyone is going by like EOS769 that outlines this, nor will there be any need for this due to the inherent differences in the protocols.
The approach to ERC721 is to me like the approach to RAM. There are many ...
In fungible tokens you track number of tokens per an account.
In non-fungible tokens you track individual token per account.
The latter is the only way to do non-fungible tokens - you need to track an individual token, as it would not be non-fungible otherwise.
You cannot compress the memory cost beyond account:token id pair, so there is no way to reduce ...
As Nat implied, there is much more flexibility in EOS and thus many ways to implement NFTs. If you accept a fuzzy definition of NFT, many games (like those linked above) already have NFTs.
There are effort at standardization for at least three reasons:
1) use of common market places that exist outside the game or application
2) making it easier for ...