This is an improvement over the previous SCADA article
Dan cited a specific implementation of SCADA software, which makes more sense to me than SCADA itself having vulnerabilities. I think that the previous article's gone through some editing, too.
It's still not clear to me whether this vulnerability is exploitable by folks on the street as such, or by insiders only. This depends on whether there are external access points to the system, I suppose. Pretty easy to mitigate those. Again, I'd be more worried about insiders than external h4x0rs.