Alex Kessinger does some back of the envelope math to estimate how big the market is for total people interested in using an RSS feed reader (like Google Reader, not like Flipboard) and how many of those people are likely willing to pay for their feed reader. (Via Brent Simmons.)

I think Alex is in the ballpark.

On one hand, you could say his numbers are conservative because it’s fair to say that in light of Reader shutting down, people are probably more motivated now to pay for a good feed reader service (I certainly am). But on the other hand, you could say his numbers are generous because how many people who’ve been using Reader will just stop subscribing to feeds altogether or else set up a Flipboard account or Twitter list?

So we know there’s a market. The big question in my mind, who’s going to bring some remarkable innovation to the table?

How Large Will the Paid Feed Reader Market Be?