The stuff about Cahokia and the sophistication of the pre-contact North American civilizations is spot-on. Starr's spent a long time reading up on that stuff among other hobbies and has given me various bits of info over time.
The buildings they built may not have as durable materials as the south or central American civilizations (so, not so many massive obvious monuments), but the larger North American societies were every bit as organized and almost comparable in size to the Southern ones.
It's like, when you learn the history of Africa, you learn that Europeans just showed up about the worst possible time. The large structured empires had fallen, and Northern Africa was in something of a warring states period. That's a huge part of why Africa's been on the receiving end for so long. But even Africa didn't face the devastation the native North American population faced. Not only were several inter-national (as in Native nations) heating up, giving the Europeans plenty of local conflicts to exploit (a pretty standard pattern), this series of horrifying plagues came in and wiped everybody out.
Actually, looking over that article, all six points are a good summary of real historical fact. It's Cracked, so hey, they're being Cracked, but it's all solidly grounded in the currently-accepted-by-archaeologists-and-research-historians truth.
Well, except for the bit about "Two Native Americans shipwrecked n Holland in 60 B.C.". That's not one I've seen before, and can't find a corroboration for that anywhere but the one book they quote.