I like Duotrope, but too many of their listings have no or little information. They need to step-up their game before they ask everyone to pay for it. I say that as someone who voluntarily subscribes.

They offer a nice service, but as it stands I don't think that it would be a good value.

Also, lets just guess that they have 1,000 users accessing the site per month: that's a revenue jump from minimal (due to ad income) to $60,000 per annum (plus whatever ad income they get). It's hard to believe that they'd improve the value of the service to that level, even if it's calced at just $60 per user per year.

IMO they need to be more thorough and up to date with their listings, too. I've seen quite a few erstwhile publishers on Duotrope that have changed format (e.g., electronic only), changed publishing frequency, revised the pay structure, or vanished altogether. A pay site should reasonably be expected to provide current and accurate information.