FBI Says Terror Probes Aren't "Informant Driven... This is the Real Thing"

In the raids against possible Islamic terrorists in Queens and Denver this week, a former senior counter-terrorism official told the NY Daily News that "This is not some ... FBI informant-driven case. This is the real thing." Is he implying that cases supported by evidence gathered by informants are not as credible? That's how we read it, at least. Juxtaposing that quote into the context of say, the Green Scare or the RNC8 case makes things very interesting. How come Marie Mason has to do 20 years if she wasn't "the real thing?"