I thought that might be the case (or he has just been bragging to impress his mom).
I also thought that it might have been laziness on the part of the article writers ("Hey, Fred, can you think of a really big number" "Yeah, 857,500,000" "Thanks, that'll do nicely"). I don't trust anyone after Jason Blair
Regardless, being repsonsible for about 1/4 the volume of US spam is quite an achievement for a guy who still lives with his mom.