At around 6pm UK time yesterday, Apple CEO Steve Jobs announced the tech world’s least-secret secret in his keynote speech at Apple’s annual Worldwide Developers’ Conference (WWDC), when he officially unveiled the new iPhone – designated the iPhone 4.

And, equally officially, I must now buy one. iWant, if you will.

There were no real surprises here. This was largely the same iPhone which tech website Gizmodo unofficially revealed to the world several weeks ago, after a prototype was left behind in a bar by an Apple engineer. (Serious oops.) The only thing we didn’t really know was its name, with many commentators incorrectly predicting ‘iPhone HD’.

As expected, the new features include:

• Higher resolution (960 x 640) screen
• Better (5 megapixel) camera, including LED flash
• 720p HD video recording
• The same A4 processor found in the iPad (i.e. significantly improved speed)
• Improved battery life (desperately needed, as my iPhone 3G typically requires charging twice daily)
• Updated operating system, iOS 4.0, allowing proper multitasking

As an iPhone 3G owner, for me the biggest addition that pushes the new model across the threshold from nice-to-have to must-have is the enhanced 720p HD video-recording capability.

Although the existing iPhone 3GS already has a 640 x 480VGA video camera – my 3G model only has a still camera – that wasn’t quite enough to make me trade up when my current contract expired in March. Despite the obvious benefit of having two devices in one, the basic VGA capability just didn’t cut the mustard. I already own a Panasonic HD camera with full 1080p, but I do have a definite need for capturing those little spontaneous moments with the kids when I don’t have the ‘proper’ camcorder easily to hand – which, let’s face it, is pretty much always – and would much prefer to be able to shoot in HD. I did briefly consider purchasing a Flip, but I couldn’t justify either the expense (at least £130) or the hassle of carrying around a second pocket-sized device everywhere.

But now I can have two-in-one, courtesy of the iPhone 4. (The new HTC Evo 4G also has 720p HD video, but a slightly lower resolution screen.)

I am hugely excited, and looking forward to the opportunity to put my order in in advance of the June 24th US/UK launch date, despite UK pricing and tariffs having not been confirmed yet by the network operators. We do know that there will be two models: 16GB and 32GB, priced in the US at $199 and $299 respectively, so a straight 1:1 dollars to pounds conversion will probably not be far out, with incentives likely for existing customers to reduce the likelhood of switching.

Whatever. Count me in. The iPad is my must-have gadget of the year for the home, but the iPhone 4 is the one essential communications device which will go everywhere I go. iWant. iWant. iWant!