[cdh-user] Services on YARN

If anyone knows, is there a plan in the works to handle services on top of YARN separately from short lived apps like MR jobs. I even hear that HBase will be a service on top of YARN. Impala via Llama is one. I want to know if YARN will section off resources for these services to have permanent residence with a guarantee of resources, or will they be equal citizens with any other app in reserving resources from YARN and be destroyed upon completion of a task. If latter is the case, then wouldn't it make sense to not have these "services" not be services anymore? Shouldn't they be similar to how Spark is or MapReduce v2 is, where both master and worker roles are spun up in YARN containers at runtime?