I'm not sure that I should be outraged about this. We're definitely more used to thinking that our handheld stuffs aren't open platforms like PCs. And of course I also have a sense that where one skilled hacker has a will, there is a way.
I'd rather deal with an open ecosystem than a completely closed bullshit setup like Apple has on its istuff, even if it means that we have to deal with more security issues, but I can absolutely understand the case that can be made for tight controls on user experience as well.
At the end of the day, I probably will wind up with a Windows 8 ARM device, if only because the people I work for have no problems keeping me surrounded by gadgets. I'm kind of looking forward to it; it's not like Windows has changed all that much since Windows 2000 came out all those years ago.
Vaguely related thought: Why the hell aren't there any Windows Mobile tablets?