Greentech Media’s research group recently released a free 145-report on smart grid. If you are new to smart grid, it’s a good tutorial on the issues. It features a helpful taxonomy  of building blocks of the smart grid.
And it’s a handy reference guide to the vendors with profiles on over thirty companies that are active in this area.
The report provides an overview of dozens of issues in this area, but one that stands out for me is the persistent challenge of crafting a business model that appropriately compensates all participants in the energy ecosystem for energy conservation. The report cites demand-response vendors Comverge and EnerNoc, who are building a business out of reducing energy demand. But it appears that most utilities still don’t have an investment framework that will support investments in efficiency.
And if you want to see latest exploration of smart grid, have a look at this post. And if you know of good material on this topic, consider leaving a pointer to it as a comment.