Recent work by Feng et al from Bengio's lab focus on how attention can be formulated as an RNN ("Attention as RNN": https://arxiv.org/pdf/2405.13956) and how minimal versions of GRUs and LSTMs can be trained in parallel by removing some parameters ("Were RNNs All We Needed?" https://arxiv.org/pdf/2410.01201).

It's possible we start seeing more blended version of RNN/attention architecture exploring different LLM properties.

In particular, Aaren architecture in the former paper "can not only (i) be trained in parallel (like Transformers) but also (ii) be updated efficiently with new tokens, requiring only constant memory for inferences (like traditional RNNs)."