Are Compete's Facebook Numbers Really That Far Off?

Last month I wrote that for the first time ever, Compete reported Facebook traffic to be greater than MySpace’s traffic in the United States. This month the company is reporting that Facebook attracted 10 million more visitors than MySpace in January. Are Compete’s numbers really far off? According to numbers that Mike Arrington published from comScore, MySpace attracted 20 million more users than Facebook last month.

So which numbers are more accurate? It’s difficult to say.