(Tangent alert.)
You know, I love Paizo. LOVE, I say.
But am I alone in not really caring much for the "Ecology..." articles? I mean, they aren't badly written or anything, but sometimes the "scientificness" puts me off.
I remember the Rakshasa article going into detail about their young. All I could think was: "Rakshasa babies? You mean, these beings of evil meet, mate, and then become parents that produce cuddly little tiger-cubs?" That image just totally ruined rakshasas for me. We're talking about demonic, extraplanar beings here. I find it much cooler if Rakshasas just are. I mean, what, are we gonna talk about balor babies next?
Same with the will-o-wisp article. It had a dissection diagram that showed wisps were really these sort of pollen-like spores with holes all over their body that expelled some sort of magical propellant. Again, I thought they were just supposed to be disembodied essences of dead people, which is far more interesting to me.
But, hey, if you like the "Ecology..." series, this a cool product. I agree with JustKim about the format and price, though.