You're right that Microsoft is only doing essentially the same thing that a bunch of other companies are doing with ARM devices. That doesn't make it a good thing.
Openly accessible hardware was one of the best things about the x86 architecture. It's gotten to a point where people simply won't accept anything less on x86 (or amd64) hardware. They've come to expect it to be openly accessible and standardized.
However, various hardware makers are trying to create a different atmosphere with ARM devices. I think that there is a good chance that eventually a standard, accessible group of devices will arrive, but that has not yet happened. That's because everyone is still trying to grab the biggest slice of pie. There's no entrenched player that other companies are willing to join together to try and fight. It's a bit like the computer market back when we had all kinds of competing systems and hardware architectures (remember the TI 99/4A, the VIC 20, the TRS-80, the Timex/Sinclair 1000, the Apple II, etc.?). It's a bit different as well of course. One difference is that at this point, these companies should know better, and so should we.
Of course, there have been a few devices, like the Nook Color, for example, which weren't locked down and you could load anything you wanted on. This seems more or less accidental, and there is certainly no standard.
Keep Up with TechRepublic