ObjC suffered greatly from not having a standard container library. What delivered GNUstep was far, far too little for widespread use, and you needed to actually pull in the whole framework.
Even if Swift will have a container library, it has tough competition that was carried though designing phase, with the result of not being composed purely of edge cases (http://blog.metaobject.com/2015/05/i-am-jealous-of-swift.htm...).
And it's not obvious how would Swift interact with C or C++ libraries (meaning: ABI and/or an equivalent of FFI).
All in all, I don't see any reason at all to use Swift as a server-side language. Extracting it from MacOS simply cripples it too much, and the language itself adds virtually nothing to the landscape.
It's in a interesting moment because react.js native is here and it's looking for that space as well, maybe it's Apple's latest shot into trying to make a technology popular.
I want whatever technology to have a Gulp package, after there's something in Gulp I can look at it, otherwise I'm not looking into it, I'm a Gulp addict :).
Best Regards,