1v1 - Bruisers and fighters will reign with an iron fist, while carries will desperately try to reach the 100 cs mark before their opponent and hope they don't get killed. Also, 1v1 monsters like Mordekaiser, AD Nidalee, Trundle and Darius will terrorize the scorched battleground.
2v2 - Still no point in picking up carries (or most supports), though we'll be seeing a lot more variety. Infamous combos like Brand+Annie and Pantheon+Xin Zhao will make the enemy duo shit themselves. Also, I predict a Malzahar+Heimerdinger combo would be overpowered as hell, with all that wave clear and kiting potential.