Hi! Congrats on your decision to go! Here's some things that I've learned, or things that surprised me!
-General Info
It's held inside EPCOT, but specifically, it's in a small event center behind a gate between Canada and the UK (affectionately called "Iceland"). It's indoors and ACed (thank god). There's a pre-reg event on Thursday, usually at one of the hotel ballrooms. Starts around noon and runs until 10 or so. You can pick up your badges, all your info, your pins, and there's trading. Thursday night is a good night for trading, pin pick-up, and meeting people and getting sorted for the weekend.
-There's lots to do!
In addition to a large trading room similar to PTNs, there's plenty to do! Trading boards and entertainment will be going on. They give a schedule on the back of your pass, so check it out and decide on your "Must See" events.
-The RSP
If you don't know, you'll be filling out a RSP (Random Selection Process). Basically, as you've probably seen, there's a pin catalog of pins released for the event. Since there's so many of us (usually around 1,000), and so few pins, they make us put our "wants" down on a list, and they run it through a computer system to pick who gets first buying rights. You'll pick what you want by the catalog number, and place it on the list (usually in order of how much you want it, or how limited the item is). You do it three times (for pins you want multiple copies of). Disney sends us e-mails, usually in August, of what we've "won" the chance to buy.
-Food plan!
Make sure you have a food plan! Some people don't like leaving the event, so they buy the boxed lunches or bring their own food in. There's fish and chips close, as well as a small chicken nugget kiosk. But it's a lot of hours to not get some food in you. Even if you're excited, don't forget to feed and water yourselves!
-You will be overwhelmed!
I came out of my first event completely poleaxed with the number of pins out there I didn't know about! Some of them have very high secondary market values! So try not to feel bad if you see a lot of stuff that you can't trade for quite yet- it takes time to gather the kind of arsenal that will you get older/rare pins. So try to trade, but if you can't, take note of them for the future, and appreciate their beauty, as if you were at an art gallery. You'll see some AWESOME pins! To that end...
-Bump up your traders!
If you can afford to, find some variety for your traders. Paris and international pins do well, as do old Disney Auctions or ds.com pins, especially if they're of popular characters. And, despite what people think, you CAN grab some for close to cost. A small lot that has some DA or DS.com pins is a good idea- just be careful that the seller is legit!
-Dogs!
If you come early enough, there will be sniffing dogs at the gates so you don't have to unload your pin bags. I am not a morning person, and I always have to unpack my luggage. -_-
-Luggage restrictions
This year, Disney is really enforcing their park-wide bag restrictions. You can have ONE bag, but that "bag" can be a piece of luggage (with many pin bags inside) up to "24 x 15" x 18", and the dimensions can go any way.
-After Parties
There are usually multiple pin meet-ups at surrounding hotels or restaurants after we get out of the event. We'll start seeing them pop up there soon.
-Personalities
For the most part, despite all the different personalities, everyone is nice and polite and having a good time. But with any social situations, sometimes there are people who are upset, or don't play well with others. I don't encounter them often, but if you happen to get someone rude or short with you, just shrug and move on. Don't let them run your first event! Chances are good it's not about you at all, after all. I know it's hard to shake off negative encounters (wherever you are or whatever you're doing), but they happen, so just try to roll with it. I wouldn't worry about it, though- I have gone whole events without a single bad encounter!