I have the FZ150 and was hoping Panasonic would see fit to use this sensor in the next generation of travel zooms. It appears they did; but in the ZS15 instead of the top model.
However, that's fine with me. I don't shoot video, and don't use the GPS feature on my SX230HS. Meanwhile, the ZS15 has a 3" high resolution screen, the good lens from the ZS8/10 with nano-coating, speeds from 60 seconds to 1/4000 and wellshaped front grip. It's also starting at $75 less than the top model.
However, I'll have to spend that $75 for a spare battery and a charger for it; as it appears that Panasonic has reverted to in-camera battery charging from a USB port or the supplied wall adapter. I really dislike in-camera charging as it's usually much slower than a dedicated charger, and you can't use the camera while a battery is charging.

It actually works against the camera owner buying a spare battery if you think about it. Hopefully Panasonic will offer an optional battery charger.
I mentioned above that I own a Canon SX230HS. It's a very nice camera with a slightly faster lens than the ZS15, a 3" LCD of medium high resolution, and a battery charger. The two issues against it, the lack of a front grip and the popping up flash, have been fixed or worked around. I find 28 mm equivalent is wide enough. So, in the end it comes down to why would I change to the ZS15? I keep asking myself that and the one thing I can see that might make a difference is the reported lightning fast AF, even in low light.
Jerry