Good entry points to reinforcement learning literature?

I realize that there is a reinforcement learning subreddit, but it looks pretty dead, so I figured I'd try here first.

I haven't really touched reinforcement learning since an intro class in grad school, and am trying to get caught up to speed on what's current in the field these days. I've read through Powell's "Approximate Dynamic Programming" and re-read the Sutton and Barto book, so I feel like I've got a decent handle on the broad strokes, but they're also both high-level and semi-introductory books, are both a few years old, and are widely-cited enough that looking up papers that reference them isn't really informative.

So given that, can anyone suggest the major groups/authors/conferences to pay attention to, point me to what the major open problems are, and suggest any specific 'must-read' papers from the last few years? I'm specifically interested in nonparametric approaches and POMDPs, if that helps narrow it down a bit.

Thanks in advance!