Mesosphere Marathon, which sits on top of Mesos, makes doing long-running services easier; it starts services, restarts them if machines crash, etc etc. Where Mesos is the resource schedular, Marathon is more like a *nix init system.
Aurora is supposed to do much the same thing, but is in Incubation at the moment. There's also "Singularity", which does a bunch of stuff including managing long-running services and one-off services through an HTTP API and webapp.
Mesos is supposed to be treated sort of as a "cluster kernel", with "frameworks" which sit on top of it and use it to schedule things. It's a lot more versatile than "I want to deploy a bunch of services" - it's more along the lines of having your own EC2 that you can request resources from on-demand.