Yup, that's how I see it, we don't have the information to know if this new ARS chip that would be implemented on the new iMac would be a transitional chip towards a more developed, affordable... one which would revolutionize personal home computing, or eventually a very good one outperforming current Intels. Or not, just a chip offering a better cost/effective more profitable option for Apple, which for being in "development" phase might be buggy and troublesome compared to the current Intel offerings that have been working on computers for more than a decade. Would Windows make something to compatibilize these new chips? Not that I'm using any Windows based apps on my Mac, but still compatibility is desirable.
On the other hand I'm with Hi-Wire that the current iMac line is being outperformed by more affordable options mounting better and more energy and heat savvy options. An intermediate upgrade of the iMac line keeping Intel architecture with better performance/price graphics and more affordable SSD, perhaps more RAM, would be my preferred option. Again we lack the information.