Hyper states it very well, exactly my sentiments. The IDB forums are dominated by the more elite players, since battledoming is one of the most expensive pastimes in Neopets. They are also a lot more serious and competitive, and the atmosphere is less light-hearted. I like the IDB forums for the competitive games, though, they are very fun.
PPT is nice in the way that the people here more on the average side and are not too serious about Neopets, you can find many people discussing about other issues too. It is also more active and friendly, IMO. But if you are a serious diehard Neopets player, who takes thing very seriously, you may not like the atmosphere here too much (the battledome board here is like a pond of still water, and most people only post in the lab ray sticky XD). People here are relatively more focused on the less competitive aspects of Neopets like painting pets, petpet matching, flash games, which may be seen as artificial and pointless by many BD'ers/elite players.
An interesting side note: There seems to be more females than males on PPT, but the opposite on IDB forums. That may account for the difference in atmosphere - boys are more competitive on the whole and are less inclined to be interested in making their pets pretty and such. They'd rather spend time making np and investing.
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