I honestly don't think there will be anything that will surprise anyone at Worlds. Most of the decks that can compete people have heard about already. This metagame is so balanced that anything could work really. There is no top deck out there, so you can't build a deck specifically to beat another deck You'll just lose to all the others. Here are my options right now:
-Gorebyss variant: I've gone through a lot of these... Everything from Arcanine to Vileplume ex. The ones looking the best right now are Medicham and TA Lanturn. Fun to play, swarm fast, and beat Blaziken and Gardevoir most of the time. The TA Lanturn variant is more focused on beating Metagross, while the Medicham one is focused on beating Shiftry. One of these is looking to be the best decision for me so far.
-Walrein/Milotic: I'm getting a little scared to play this again. It just flat out loses to Metagross, loses to Shiftry probably 65% of the time, and can have problems with Gardevoir sometimes (although Walrein does beat Gardevoir about 70% of the time). Still absolutely crushes Blaziken, which is why I still think this has a chance.
-Sceptile: I really think this deck could make a showing. The thing I really worry about is that it's pretty much an auto loss against Blaziken. Still, it beats Gardevoir usually, is pretty much even with Metagross and Shiftry, and crushes Walrein and Swampert. This deck is definitely something to think about.
-Kabutops ex: I highly doubt this could work. However, with Grass decks pretty much out of the metagame, it could do something. Lightning is still something to worry about with those Lanturns going around (damn you Pat =P). I haven't tested this at all, but I think with the addition of ATM Rock + SK Kabutops, it might be able to do something. Again, this really shouldn't work, but I'm just throwing ideas out there.
Well, those are pretty much my choices. I'm going to Worlds to have fun mostly. I don't care if anyone knows what I'm playing. Nothing is going to shock anyone. Anything can win. Even Team Magm... well maybe not ANYTHING. ;x