The Galaxy ToolShed makes it easy for tool developers to make their tools available to Galaxy instances, and by versioning and managing tool wrappers and dependencies it greatly improves reproducibility. The ToolShed is described in an open letter published by Genome Biology in February.
Galaxy Data Managers automate management of datasets that are required for Galaxy Tools such as genome sequences, indexes for aligners. With data managers, adding reference data to a Galaxy instance is vastly simpler. Data managers are like any other tool, and can thus be versioned and distributed through the ToolShed. A paper describing data managers was recently published in Bioinformatics