This is exactly the reason why Apple stopped numbering the iPad releases; this is a relatively minor spec refresh, NOT a brand new device. Apple needs the flexibility to keep their products competitive on the spec sheet in the face of constant Android releases. Being locked into yearly refreshes is a competitive disadvantage.
No matter what Apple does they can't win. If they limit themselves to once-a-year updates, they are criticized for selling year-old technology at premium prices. If they update their products mid-cycle, they are criticized for making the previous model "obsolete" too soon.
Doubling the CPU and GPU speed is not really a minor upgrade. Going from the 2 to 3 was a minor upgrade. This is a major upgrade that just segments the Apple products more. Developers can either take advantage of the extra speed or become like Android/PC developers and code to the bottom tier devices.
Please. The iPad 3 added an upgraded CPU/GPU , Retina display, 5 MP camera, HD 1080p video recording, and LTE. All without sacrificing battery life and thinness. It was a complete re-engineer. This new revision
simply upgraded the chipset and front camera. All the hard work and major selling points were added in the 3.You guys cried when Apple markets the 4S as a new model saying it was nothing but a minor speed bump. When they treat the revised iPad as a mid-cycle speed bump, you cry that it's a completely new model that came too soon.
The CPU was not upgraded between those versions. Only the GPU was upgraded was the four SGX543 GPU cores. Every bit of that performance gain was lost due to the Retina display. In fact my understanding is that was the only reason the GPU got the upgrade. So even though you had more GPU horsepower you had the same performance.The new CPU is clocking 200mhz faster which gives twice the performance of the prior iPad in the CPU department. Since they only had to bump it up a measly 200mhz (150%) to get that performance I would assume the major architectural improvements give the rest of the improvements.
The GPU is an unknown as far as I know but the guess is it still runs the same four cores just bumped up from 250mhz to 500mhz.
If you look kup the GeekBench scores for the iPad3 vs iPad2 you will see the two devices are equal. You will also notice on the GlBench that the iPad 2 actually has better graphics performance than the 3. This is due to having to drive the Retina display. This is clear when you look at the off screen display scores of the iPad 2 vs Ipad3.
Now go look at the same benchmarks for the iPad3 vs iPad4. The ipad4 more than doubles the iPad 3 score on this benchmark.
The minor upgrade was in the iPad 2 to iPad 3 since it was basically the same performance wise. The major hardware change to the GPU was simply to drive the Retina. Now with the iPad 4 you have a true update to the iPad 2 performance wise.
So really everyone that bought the 3 got the minor upgrade. The new buyers of the 4 are the ones that won the upgrade sweepstakes.

You are correct that the CPU in the A5X remained the same, I stand corrected. The chipset was upgraded, but the upgrades were on the GPU side.
At the end of the day, only a spec geek would think that iPad 3 to v. 4 was an overall bigger jump than iPad 2 to 3. The addition of the
Retina display, LTE,
5 MP camera and HD video recording -
all without sacrificing performance, battery life or form-factor - marks a huge jump in functionality for the user that far outweighs a single CPU increase.
The iPad v.4 includes a new generation chipset, but it is not a new generation of device. It is a faster iPad 3.
I would rather have a tablet that performs well and gets work done faster. I also prefer smoother graphics in my games. That makes me heavily lean toward the better CPU/GPU.
Retina Display - Nice but not needed
The Retina display is nice but what benefit does it give you? The iPad really is to big to use as a e-reader and carry everywhere. 1080p encoded moves are scaled up so it is possible the video will not look as good as the original. If you don't scale up your wasting the extra resolution anyway.
5mp Camera-Wasted weight and space
Really? You lug an iPad around as a camera? A 5mp camera? That's still a full megapixel below what a lot of people consider the best comprise for compact cameras? Not sure why anyone would be excited about a subpar camera on a 9.7" device.
1080p Video-Wasted weight and space
Once again why are you recording HD movies with an iPad? I'd much rather use a dedicated shooter or simply use my phone that is much easier to carry around and has the same (well better) performance. Not to mention your not going to get a lot of movies stored on the smaller iPad models. Most HD at 1080p eat us almost 200mb per minute.
So truthfully I see no jump forward from the iPad2 to 3. They added a bunch of things that really did not mean a lot in the long run. Now that they released the 4 there is a true upgrade from the iPad 2.