Is iPhone 4 the Biggest Leap Since the Original iPhone? Probably.

The first analysts’ notes on Apple’s new iPhone 4 have begun rolling in and they sound a common theme: While not the revelation it might have been (for obvious reasons), the device may well be, as Steve Jobs claimed Monday, “the biggest leap since the original iPhone.”

“While the announced features of the iPhone 4 were as expected, the reality is this phone is significantly more advanced than the next best alternative,” Piper Jaffray analyst Gene Munster wrote in a note to clients. “We see the iPhone 4 as the most meaningful revision since the iPhone 3G two years ago. As such, we believe more existing iPhone users will be inclined to upgrade to the iPhone 4 than we saw with the iPhone 3GS.”

Munster notes as well that gee-whiz features like iPhone 4’s FaceTime video calling app, its HD video camera and iMovie video editing software are together creating an integrated experience that typically requires multiple devices. “The bottom line is the iPhone is taking unit and dollar share from other device categories,” he writes.

Indeed, it was hard to watch Apple’s (AAPL) demo of the device’s HD video camera working in concert with iMovie Monday and not think that it’s going to eat the Flip Video camcorder and Kodak’s (EK) Zi8 alive as soon as it arrives at market. And things don’t look much better for Google’s (GOOG) Android “superphones,” though obviously, there’s a much bigger battle to be fought there. Certainly, the company and its hardware partners have some serious work to do in the months ahead.