For the longest time, the Edutainment Storygames were our greatest asset -- and, as you described, well written and fun. Back when the site was getting off the ground, we figured Content First, Users later, and payed a bunch of the Google Answers folks (mostly professional researchers/writers/etc) to make them. Fortunately, it seems that the writing/content is finally starting to catch up to these.
So why did we commission edutainment? It's chocobot's favorite category and was the only request that seemed to get a response on google answers (researchers, you know). Choco is sad to see that no one else seems to like the category.
Another thing to note, Edutainment will eventualy go away. Wehn we implement TAGS (see the FWW), an "educational" tag will be added. Both choco and I feel this will encourage more authors to include educational content in something SciFi (science related), Fantasy (mythology related), etc.