You did noticed that:
1. This thread's from July
2. He wasn't making up things, but agreeing with what the main post which said: "customers have told us there may be something wrong with our inventory of the item, the way we are shipping it,"
Before the edit added more info around 6 hours later (back then).
The statement on the page reads: "While this item is available from other marketplace sellers on this page, it is not currently offered by Amazon.com because customers have told us there may be something wrong with our inventory of the item, the way we are shipping it, or the way it's described here. (Thanks for the tip!) We're working to fix the problem as quickly as possible."
For what is worth, Skylanders for the 3DS had the same message until yesterday. For a moment at the thread, it was assumed that it was because they have the game listed, with the wrong information (has the same info of the console versions, but he game's different). But now is back...but still with the same (and wrong) information.
So, well..who knows what's going on. Nearly every retail/online/etc. place is still selling it; so it seems to be something with Amazon and 3DS stuff; more than an actual problem.
I want to make a proper response, but I can't even remember the context to the post I made 3 months ago. I think it was "Amazon says product isn't being sold due to being damaged in shipping, maybe, you know, amazon is telling the truth?"
Or are you quoting me 3 months later to make fun of my tag?
Yep, I think longer actually. You could buy it through 3rd party sellers but Amazon itself wasn't selling.
EDIT: I think started in July, was in stock temporarily from the time between July and October (although I believe there were many times where it wasn't in stock) and then from October until now it has pretty much been out of stock the whole time.