Okay, you're a 'short-timer' now! I know you are excited!!!

We just got back and had a great time.

We drove past the surprise hotel a couple of times and the kids were very impressed and wanted to know if they could stay there sometime!
You will probably have the same weather we did - highs in the 90's and showers often, especially in the afternoons. Most days that helped because it lowered the temp a little and cleared some people out of the parks, but one day we had showers on and off all day, and every time it felt like an oppressive steam bath afterwards.

Just keep the ponchos handy. I also had a very small umbrella that I normally carry in my purse, and that helped a lot. I also discovered that my rubber beach sun visor, worn over the hood of the poncho, kept it from flying off my head and kept the rain from running down my back!! That was a tip from someone on DIS, so thanks, whoever it was!!
The only thing we missed that I really hated was Wishes and Spectromagic. We didn't have hoppers so the two days we were in MK the rain interfered with us. You will get to see the Summer spectacular fireworks and the Electric Light Parade, so that will be lots of fun too!
The very best thing about our trip was the "magic" fast passes that we got for volunteering. It was so great to go to those rides and get IMMEDIATE fast passes, even when they were all gone for the day. There were 8 of us who had done it so we had one for every day and one to spare that we used for the pins. We rode Toy Story Mania THREE times using those!! (We had gotten a regular FP for ToT and ridden RnR straight when we got there so didn't need them for those.) They would always have one FP terminal for the special FP cards even when no one else could get them. (Kali River wasn't using FP the day we were there, except for us.) The last day we even got to give some FP's away as we were leaving Epcot, because we hadn't used them all. That was nice, too. I hope they figure out a way to do that again in the future - we were spoiled! We did the Linus Project like you did because the kids could do it too. It was just a great program all around.