My guess is that the sensor of the D3200 will spread to higher spec Nikon DX bodies later this year; call them D5xxx and D7xxx class. So those who want auto-bracketing, MLU, a higher frame rate, a more rugged body, or such might benefit from waiting a bit.
P. S. since Nikon (like Olympus) does not do all the design and fabrication of its sensors in-house, it (like Olympus) is often rather coy about the origins of its sensors, and the internet fills that information vacuum with all kinds of wild speculation, much of it flattered by the name "rumor". Since Nikon (again like Olympus) does do a significant amount of R&D on sensor technologies, as shown by patent searches, it could well be that the sensors used are variants of the core designs from Sony (respectively, Panasonic), but clues like the consistent closeness on pixel counts, pixel sizes and most performance measures suggests at least a close relationship to sensors from Sony (resp. Panasonic).
So why worry about the sensors' origins? The performance measures are both far more important and easier to learn.