If the marginal increase in zoom range isn't enough to tempt you there are a couple of extra improvements, but they don't amount to much. The most significant is the new LCD monitor. It still measures 2.5 inches with 230k dots, but it now has a much wider angle of view, around 170 degrees both vertically and horizontally, which is very welcome.
In shooting mode the FX37 has several extra scene modes, but they are of marginal use. The Transform mode for example stretches the image either horizontally or vertically either a large or small amount. I personally can't think of anything for which I'd ever use that one. The Pin Hole (vignetting) mode and Film Grain (grainy high-contrast B&W) modes are slightly more aesthetically pleasing, but not the sort of thing you'd want to use too often.
The FX37 incorporates a feature borrowed from the TZ4 and TZ5, the Clipboard mode. In this special shooting mode the image size is reduced to 2MP and the image is stored in the camera's internal memory rather than the memory card. The idea is that you can use this mode to copy maps, timetables and other information and keep them stored on the camera. However I can't see why you couldn't just use the normal shooting mode for this. 1GB SD cards are ludicrously cheap these days, and one of these is enough for nearly 200 shots from the FX37, so it's not like storage space is at a premium. Also, wouldn't you want to copy maps and other documents at the highest quality, so they're more readable? This "feature" feels more like a gimmick bolted on for the sake of it.
Apart from these and a few other very minor differences the FX37 has exactly the same features and options as the FX35. They're very good features, such as Panasonic's excellent MegaOIS optical image stabilisation system, a good movie mode capable of shooting 1280 x 720 HD video at 30fps with mono audio, and the Intelligent Auto system, which chooses the scene mode, exposure mode and ISO setting for you depending on the scene you're trying to shoot.