I took a quick turn around the top tables to see what kinds of decks the 5-0's were playing. Hardly scientific, but enough to give me a rough feel for what the common builds are.
The first thing that stood out is that very few players are playing black. It's not hard to see why. Take a look at black's commons in Born of the Gods[/URL]. It's like Asphyxiate Visits the Island of Misfit Toys, and you get three packs of that. Worse for black, a lot of its best cards in Theros ask for a heavy commitment, so your mana often won't work out the way you'd like. The common thread among those willing to sleeve up swamps is a wealth of good removal. I saw one player lucky enough to fan open a starting hand that included Hero's Demise, Gild, and Keepsake Gorgon.
Now, it first glance it looked like the other four colors were evenly represented, but once I started tallying deck types a surprising trend emerged: The two most popular decks by a wide, wide margin were Red-White and Blue-Green. I doubt it's just that players are opening a disproportionate number of Kiora's Followers and Akroan Phalanxes. My gut instinct is that red and white are the two most aggressive colors, so they match up the best, and that there is some similar harmony for green and blue. Maybe creatures that hold the ground and an air force?
Also worth noting is that players do not seem to be stretching their manabases. Only a handful of decks dipped into a third color, and often for little more than a single spell and an off-color activation. Those playing green could afford to be a little more ambitious, thanks to Nylea's Presence and Karametra's Favor.