I'm not really up to date, but a couple recent papers that I found interesting were:
In theoretical distributed computing, The Space Complexity of Concencus From Swap [0] solves a problem that has been open for a couple decades, and won Best Paper at PODC 2022.
In quantum complexity theory, MIP^* = RE [1] was really big deal when it was published in 2020. It got a (relative) ton of press coverage, and there are lots of articles and blog post available that give a high-level of the result and techniques used. I like this one [2] from Quanta Magazine.
[0] https://dl.acm.org/doi/abs/10.1145/3519270.3538420
[1] https://arxiv.org/abs/2001.04383
[2] https://www.quantamagazine.org/landmark-computer-science-pro...
Maximum Flow and Minimum-Cost Flow in Almost-Linear Time
Best to look at recent papers at arxiv https://arxiv.org/list/cs/recent
You can have a look at Baez's work
https://www.azimuthproject.org/azimuth/show/HomePage https://johncarlosbaez.wordpress.com/
computational category theory. Lots of cool stuff there.
HVAC
Lisp is making a comeback
[dead]
Most bleeding edge stuff is going to be designing the compute pipelines/hardware for ML.
Koka [1] has “algebraic effect handlers” which are pretty cool. An alternative to monads for modeling effects in a sound way.
Lots of advances in theory of gradual typing. See with by Ben Greenman et al.
That’s just stuff from my neck of the woods. (PL) I would recommend reading stuff from POPL or ICFP or OOPSLA.
[1]: https://koka-lang.github.io/koka/doc/index.html