When you crunch the numbers as people have done before, 1 bil entries per day would push the price of factoids up 100x. But looking at the current figures of 4.5 mil entries in total, there isn't enough entries to even justify the current price of a factoid. I expect the entries to increase in the future obviously, but to what extent is realistic? How many entries would dept of homeland security bring in?
A factom employee said they've held talks with companies that would need to input a billion entries per day. Whether anything comes from those talks, who knows (I suspect they will in time). But the discussions have been happening.