This merits some attention: "Neuroscientists reach major milestone in whole-brain circuit mapping project".
The data consist of gigapixel images (each close to 1 billion pixels) of whole-brain sections that can be zoomed to show individual neurons and their processes, providing a “virtual microscope.” The images are integrated with other data sources from the web, and are being made fully accessible to neuroscientists as well as interested members of the general public (http://mouse.brainarchitecture.org). The data are being released pre-publication in the spirit of open science initiatives that have become familiar in digital astronomy (e.g., Sloan Digital Sky Survey) but are not yet as widespread in neurobiology.
It's a press release from Cold Spring Harbor Labs, giving some background on the project and its use of a "shotgun" mapping approach for neuronal connections. For me, the most exciting aspect of the open access data is the potential of running analyses across different datasets, such as the gene expression element of the Allen Brain Atlas. Drawing conclusions may require a sample more representative of different stages of ontogeny than is now available, but these will be the next logical step -- understanding brain structure really requires us to understand how it develops.