Convention season is in full swing, and European conventions are about to be underway as well. This means that we'll be getting some information on Khans of Tarkir from our overseas friends soon. And, perhaps, sooner than anyone anticipated - MTGSalvation.com Rumor Mill user th3B0At1SD03K1Ng says an accidentally-cracked Speed vs. Cunning deck revealed to him a reprint of the first-ever white-black-red card to be printed as well as the mana fixing land cycle from Khans of Tarkir:
Hasbro workers also made a mistake an brought the new Duel Deck "Speed vs Cunning" from their German headquarter and opened it.
3 Color tapped lands like in the Alara block were inside. I have no pictures of them.
I can tell you that there was a reprint of Fervent Charge, i spotted it as i have that card also in my collection.
If true, this is welcome news; tricolor lands rather than dual lands are entirely appropriate for a wedge set. "Enters the battlefield tapped; Tap: Add C, D, or E to your mana pool" may be an obvious route to take (the allied-color arc version of this cycle was, as stated, in Shards of Alara), but it's a reliable one, and apparently indicates that R&D wants a relatively slow Limited environment for Khans of Tarkir, with the speed-obsessed Mardu Horde clan apparently excepted.
Fervent Charge also has plenty of fans, especially among those (like yours truly) who were playing when Apocalypse was released and were blown away by the very concept of wedge tricolor, although wanting more than just one, rare, card per color triple in the set.