AT says it's a "cH-style screw-down 4-pin connector"
The only pictures i can find for it are from AT, so it doesn't feel/sound like anything all that standard.
The variety of beltpack connectors for wireless is a personal pet peeve of mine, so the idea of adding another connector to the mix does not make me super keen on using AT systems....
I was just about to post that same picture!!
I have no clue as to why they would change the connector on a well established wireless system that has been around and working well for years.
Just looking at the connector it looks HIROSE like with the four pins only with a completely different locking concept.
Maybe it was cost, but the connector doesn't appear to that much simpler in design.
I always felt the AT 3000 series was at the sweet spot of good price point and performance.
So far I have not heard any pricing info on the new series.