I've been contemplating a little plan for my solo day before Jen arrives. A 4 Parks/1 Day type of thing. I'm not 100% sure I want to do that but I thought it might be a fun little challenge for me to do that and experience at least one ride or attraction in each park.
The Park Hours for Thursday are:
Magic Kingdom: EMH's 8 - 9AM, 9 - 8PM
Epcot: 9 - 7PM, 11 - 9PM
Hollywood Studios: 9 - 8PM
Animal Kingdom: 9 - 5PM
I think I would start at MK, then over to Animal Kingdom, from there to Hollywood Studios and then end at Epcot. It would probably be an exhausting day but right now it sounds like fun. I think I'd spend more time at Magic Kingdom than any other park so I don't know if I should go there first or last. I like getting that extra hour in the morning but I don't know. My other question is about Soarin....do they keep that ride open until 9PM when World Showcase closes or would I have to make sure to be in line before 7? Any thoughts? Any advice?
I think it is a cool idea, but I think I would also be afraid to spend too much time in transport...
I think it depends on which attractions you want to ride at each park on where you need to start.

If you don't want to wait for ages for Soarin, I would start in Epcot, I think this and TSM get the longest lines.

But if it is a Fantasmic day, it would be even better to start at DHS...
So what about this: DHS at rope drop, take boat over to Epcot, enter through IG (I think there is also a bus to the front entrance of Epcot. There is definitely one to the TTC and you could take the monorail from there), if things work out you might be able to get a FP for Soarin with a time not too far away, get some lunch and check out the Seas and Spaceship Earth, then go on Soarin, exit Epcot at the front, take bus to AK, then from there either take bus to TTC to bet ferry or monorail to MK (depending on how you got to Epcot, you would be able to incorporate all methods of transportation in your day as well) or take the bus to the Contemporary and walk from there.
If you want to do Epcot in the evening, don't worry. A lot of Futureworld attractions are open until 9pm, including Soarin.

I think the others that are open are Mission Space, Spaceship Earth and Test Track.