Hmm. Well, in my case the info I use for my Windows Live log in was only used on whatever sites required it. The only ones that I know of are the Xbox, Xbox.com and there is one that escapes me now. My password was different so I'm not sure how that's my fault?
And the guy in the Kotaku article, how was it his fault?
I can see if you use the same e-mail and password on myriad sites, then yes I think you're opening yourself for failure.
The crazy thing is why on Earth anyone would want these accounts in the first place, just for the prestige of having a respected account?!? I could undertsnad the whole FIFA debacle because of the money aspect with Ultimate Team. But people paying actual money just to have a gamertag?
I've never heard of this on STEAM (But I don't play on PC) or on PS3. Both have systems in place where you earn a reputation, collect virtual accolades, etc. But you only hear about this shit on Xbox.