I don't really agree when it comes to finance. The difference is you can't argue with mathematics, something that you can't see for yourself on CNBC. Top bloggers in the financial world have to go the extra mile to prove what they're saying is truth, opposite of tv. The hosts of these shows you see on financial networks are generally reporters with little understanding of economics, plus you know almost every "expert" on air has their own agenda.
Of course, I'm talking about more famous blogs, not something that gets a couple hits per day.