To me, it looks as though Lenovo has been trying to make the Thinkpad line more profitable by slowily adopting common components/methologies from other lines. They could have assymilated the Thinkpad designs to make the Lenovo branded products better, but that would have increased the production cost, even if only slightly.
Its evident even in the firmware, where each generation moves away from handling more functionality in hardware (think things like the independent volume control/amplifier) to using software to make it look like it still functions like a Thinkpad.
Also, completely idiotic to follow Dell on the tablet design. The latchless lid on the latitude XT was stupid, and for whatever reason, Lenovo decided to follow suit. The x220 and x230 tablets are clearly yet another step down (I've had my nose in most of the tablet models since the x41). Don't get me wrong, the speed and low power capabilities (I frequently run at 6W when I want the battery life) are superior, but I think that's more a statement of the general trends in laptops (thank Intel for the cpu/chipset). The build quality and the bells and whistles under the hood, the things that differentiated the line, are trending towards the mean.
I highly doubt that's the case. I suspect the defect/variation distributions of few if any generations of intel chips have actually matched the distribution of market demand. Going back at least to the 386, they have artificially crippled higher end models (beyond what was necessary from defects), to provide different price/feature/performance points for consumers. The SX line was just DX chips with the internal floating point unit disabled.
We might feel a little less cheated if Intel actually designed and fabricated different products so that we actually get what we pay for, and don't have to feel cheated because that new cpu is artificially crippled. Realistically, the production cost of the extra silicon is far less than the cost of designing different chips. And, yes some chips will naturally fall into the lower end models because of defects and variations. So whether or not we feel cheated, they are actually delivering a better value to the customer by artificially differentiating the models. People are accustomed to market segmentation, airfares being one major example, I suppose it just feels a little different knowing that you get a black box that is a first class seat with extra blocks added to squish you because you only wanted to pay for ecconomy class.
As to why the segmented market is reasonable, the fact of the matter is people do have different values and needs, and people want a price tag that matches those needs. Intel could charge a uniform price for all cpus, but then they would have to decide between alienating a huge number of customers by setting to high a price, or drastically reducing their profits. Say what you will about corporate greed, and even Intel's stagnation. They do reinvest huge ammounts of their profits into building new fabs, and other aspects of producing subsequent generations. Market segmentation enables them put more of the cost burden on the customers that have more money to play with and really care about the getting the performance now. Really, it most benefits the consumers that will feel cheated (I haven't heard people complaining about the higher prices of the higher end chips). If chip makers were acting with more bad faith (just look at the telcom and cable industry), then this would be more upsetting (and less about consumer value).
As for the lying issue. I don't think this has been much of a secret for the last 25 years. Its probably just a matter of more people are becoming aware of it now, people who are less familiar with the literature and issues. Also, I think Intel has been fairly stupid about marketing. The post-sale "upgrades" drew people's attention to issues that most people just don't want to know about, and probably didn't really appeal to all that many consumers. Its also a little sickening to see them put effort into developing a "secure" system that lets them sell hardware upgrades. Perhaps something like that would just work better for consumer relations if they provided a trade-up program, even if it does mean it would cost more for consumers to get the same upgrade (assuming the same profit for intel).
The meat is rotten, but the booze is holding out. Computer translation of "The spirit is willing, but the flesh is weak."