There really is a little bit of everything out there this weekend. Numerically, at least, the pillars of the format are the various builds of Caw-Blade and Valakut. With powerful, consistent draws and lots of game against random aggressive decks most people consider them the safest bet, especially if you're confident in your limited game and only need a few wins in constructed. Here's the full breakdown:
Caw-Blade - 37
About a third of these are the Hero-Blade version, with the rest banking on Emeria Angel. Phantasmal Image is popular, but by no means universal. There's even one Caw-No-Blade, run by self-proclaimed "Genius or Idiot" Nassim Ketita.
Valakut - 26
Blue-Black Control - 14
After Ali Aintrazi's victory at US Nationals, this deck is more popular than ever. Only a few copied his exact list, with most trying to tweak the numbers.
Splinter TWin Combo - 12
About an even split between those running Matt Nass's version and those not.
Mono-Red - 11
Birthing Pod - 10
These are all over the place, color-wise. The most popular version seems to be Red-Blue-Green.
Pyromancer's Ascension - 8
All dedicated combo decks, no hybrids with Splinter Twin.
Twin-Pod - 3
Tempered Steel - 3
On paper, it looks like a beating.
Red-Black Vampires - 2
Grixis Control - 2
Building on Aintrazi's Blue-Black list with Grim Lavamancer
Miscellaneous - 15
Including Blue-Green Aggro, Big Red Planeswalkers, RUG, Boros, Naya, Eldrazi Green, Blue-Black-Green Tezzeret, White Weenie, Elves, "Turn 4 Titan" Black-Green, Esper Control, Blue-Black Tezzeret, Blue-Green-White no-Pod, Red-Green Aggro, and Monogreen Poison.