What are some of the best S3 builds/champions you know of so far?
As best as I've figured things out so far, support seems to start philo+faerie, using the free ward mastery and the lack of early ganks to rush philo+sightstone, then boots, kage, ruby sightstone, aegis and then probably shureliya and runic bulwark, but I don't know about situational items or anything past that. I'm not sure if the flask is a good buy or not yet. It seems rather weak except at the very start, but you can keep it around for a rather long time, so it has some worth.
I'm starting to wonder if heal is actually viable as a summoner spell now, too. Elisia's miracle seems pretty hard to fit in there unless you're just really well fed by level 15, though, but the passive that gives extra HP seems nice now that everyone is just so incredibly squishy. And you can't just take a tiny hit out of the defense tree for a few extra armor/MR any more.
All the other active items are fun to play with too, but I'm just not sure what is and isn't good yet.
Currently the best thing about s3 is the possibility of running a support with magic pen build. MR's cost has been increased and full magic pen build is really effective.