Râu from the RS core team here. I just wanted to point out that there's a bit of a wording problem, which will cause misunderstandings if not corrected. Let me explain:
RemoteStorage is a protocol for per-user storage on the Web. It defines how both clients and servers have to behave to be compatible with it.
We develop and maintain a reference client library that makes it easy for developers to store data in users' browsers offline, as well as sync it to remoteStorage-compatible servers. It is called remoteStorage.js, and it is but one client (albeit the most popular one).
However, remoteStorage.js already has experimental support for syncing to other backends, i.e. not remoteStorage backends. There are many reasons for this, but mostly to ease the transitions for both developers and users to an open protocol, by giving them the choice to use what they are familiar with for now, and migrate data later on, whenever they're ready.
So, as such, there are no other/new remoteStorage backends. Either a server is remoteStorage-compatible, or it is not. In this case, what's actually being done is adding a new storage backend to the remoteStorage.js library, enabling Maidsafe as an additional option for app developers and users (next to RS, Dropbox and Google Drive).
Now, with that out of the way, some personal opinions:
I think--and I know the current maintainers of rs.js agree with me--that it's a great idea to turn remoteStorage.js into a more general-purpose, offline-first, unhosted storage library. And Maidsafe would be the first true opensource addition as a new backend.
I'm not keen on adding more proprietary options at all actually, but adding more opensource options can only benefit both developers and users, as well as the unhosted movement in general. So I'm extremely glad that this is happening, and we'll fully support efforts from anyone toward that shared goal, now and in the future.