You have stated this twice, but the reason why this should invoke worry seems to have been left as an exercise to the reader. Perhaps there is some sort of underlying assumption you make about someone pimping their SO score that I am not making?
Help me understand why this should worry me. There are plenty of good questions and good discussion that I've seen on SO, and the reputation people have earned has seem more often deserved than not. I don't think a good SO reputation deserving quite the heated bandwagon snarking this article produced.
Secondly it would set alarm bells: why are they so excited about their SO score? Is it intended to impress me so that I skim over the rest? (it's not the only flag I've noticed in interviews; there are lots of similar ones, you pick them up). [it'd also worry me that they haven't figured out it's not a great metric]
So what I am saying is: having a good SO score is definitely something great to mention to me. But only in passing or I would get suspicious :)
(on the other hand if I were hiring, say, an API community manager then it's an awesome metric! :) so I guess it depends)
Additionally if someone promoted themselves as "I have X score on SO" it would worry me.
(that's also before we discuss whether the ability to answer questions well on SO marks you as a good programmer or not :))