The question I've been asked the most over the past couple months was, "Should I buy the Sony HX9V or wait for the HX30V?" Having now tested and reviewed the HX30V, I can answer that question: it depends.
After all, the cameras are very similar, at least on the surface, as they have a lot of features in common and nearly the same size and weight. There are differences, but are they enough to pay more than $100 for? The Sony HX9V is currently about $300, whereas the HX30V is around $420.
The biggest hardware differences between the two -- at least those to do with photo and video quality -- are the lens and the sensor and image processor. The HX9V has a 16-megapixel Sony Exmor R BSI CMOS sensor and a 16x, f3.3-5.9, 24-384mm lens, while the HX30V gets a 20x, f3.2-5.8, 25-500mm lens and its sensor is 18 megapixels.
The HX30V's newer Sony Bionz processor and sensor help the camera perform some of its other distinguishing features. Those include capturing 13-megapixel stills while simultaneously recording full HD movies (the HX9 can only do 3-megapixel stills); improved active image stabilization for when you're shooting video while moving; extra-high sensitivity for low-light shots at ISO 6400 and ISO 12800; and Sony's Clear Image Zoom, which digitally extends the zoom range to 40x. I consider none of these deal breakers or reasons to buy the HX30V, especially the last two.
However, there are a couple of good reasons -- aside from the lens -- that you should consider spending more for the HX30V. For one, the camera does have faster autofocusing with less shutter lag in both good lighting and low-light conditions.
Also, though the bulk of the shooting options are the same between the two cameras, the HX30V has nine live-view picture effects, like toy camera and partial color, which lets you pick a highlight color and turns the rest of the photo black and white (examples of which you can see in this slideshow). The camera also has a new interface available in Intelligent Auto and Superior Auto where you can adjust brightness, color, and vividness using simple sliders as well as access some of the picture effects.
GPS is also improved with logging letting you track your photo shoot and later view the path and pictures on a map. And, again, if you opt for the HX30V and not the HX20V, you get built-in Wi-Fi.
If an extra $100 sounds like a good price to pay for a longer lens, faster AF speeds, picture effects, GPS logging, and, well, everything else that I just mentioned, get one of the new models.
The photo and video quality for the most part are the same between the models. So, if you really just want a powerful compact megazoom, save yourself some money; the HX9V is still an excellent camera a year after its release.