The beginners list of species seems kinda lacking to me. For one thing, E. tricolor was THE beginner frog back when PDFs were picking up steam - they fell out of beginner popularity due to availability. I vote they should be put on the list.
Also, P. bicolor is just as easy to care for in my mind as P. terribilis. P. auroteania has also come highly recomended as a beginner frog. I see no reason to have these guys left out!
Another thing to think about is morphs of the species - most of the species listed have incredible variety of morphs in the hobby, and some are better than others as beginners for various reasons. You don't have galacs as beginner frogs (which I understand, they can be a bit tricky) but there are some tinc morphs and what not that are just as tricky. Might be best to have a list of which morphs are best first time around, or rather (for a shorter list) what morphs of the species to aviod as a beginner (I woudn't recomend GO/Reginas as a beginner frog, yet they are a tinc...)
As for what blue dart has mentioned, keeping fresh suppliments is definately important, but the stuff like STS can stay out of it. Ed wrote a nice blip on FrogNet about "STS" which might have more to do with Vit. A than calcium - but its still a bit unknown.