4) Spoiler Season Tropes
Every spoiler season you see the same stupid arguments among the same stupid players. Here is my favorite example: any preview thread when a green card is spoiled.
[Spoiled green card that costs 6 mana]
Commenter 1: "This will be great on turn 4"
Commenter 2: "You mean on turn 6?"
Commenter 1: "You're playing green. Green has ramp, dummy."
This exchange is always present, and never productive. That's the theme of spoiler threads I guess, two players you shouldn't take advice from under any circumstances arguing over whose simplistic reduction of a card's likely impact holds more water.
If Magic Online were still around, it would have been great to have a format where you get 60 minutes to build a deck from a made-up format (such as Onslaught + Zendikar + Tempest + M12 "Constructed"). In that 60 minutes you have to figure out what decks you can build, and actually build one. The world needs to see what kind of decks these people produce. That's also how the set should be spoiled actually. All at once, in a massive Block Constructed event. Spoiler goes up at 9 a.m., at 11 a.m, you have to submit your deck, and here's the important part: later on, whenever you are commenting on which cards will be good in Standard or whether a new fatty is playable because you can ramp into it, there's a link to the deck you submitted in the Prerelease Free-for-All. If it's laughably bad, we can ignore the comment. If it looks like you cobbled together a playable deck, maybe I will listen to your predictions.