I just started to build a new python library to ease access and control of remote hosts via ssh: rcontrol. It is based on paramiko and offer a high level API to execute remote and local commands in parallel.
rcontrol is an alternative to fabric – but rcontrol is not built with the specific deployment use case in mind, do not use global variables (I really don’t like the fabric global env), is intended to be more user-friendly for tasks synchronisation (doing things in parallel) and finally is compatible with python 3.
This is actually not a Mozilla contribution. Still some part of the library share a piece of code with MozBase, because I reused the same code I wrote in one of the patches, to separate lines of output streams from a process (see bug 794984).
If rcontrol sounds like what you need, give it a try. 
Look at the README for a detailed description and more information about this tool – then at the documentation. If you find a bug or want a new cool feature please report it, or even better create a github pull request (contributions are more than welcome!). And if you like it, star it on github!