The biggest negative I have about JetBlue is the seatback TV. There isn't any (obvious) way to turn it off and it generates a fair amount of heat. I get motion sick looking at a screen on a flight; this is a little annoying.
One of the primary planning goals on this trip was to avoid dragging a kid seat down to Florida and back. We thought we were going to need a rental car for two reasons: getting groceries, and possible visiting with relatives in the area. C., however, decided that if she was meeting up with her brother he was going to be doing the driving. I found enough positive (and no negative) comments about GardenGrocer.com that I felt comfortable ordering groceries from them. Also, driving all the way out to the Publix sucks. In fact, I-drive in general sucks. No rental car + Cares Harness for A. = no kid seat needed.
GardenGrocer.com had a decent selection of foods, including some organics. While beer and wine are not listed on their website, you can call and they will add it to your order -- that's not an internet myth. I have no idea if they'll deliver anything harder; I didn't try. You can also get alcohol at the C-store in the Contemporary, as well as some groceries (their selection, however, is crummy and their prices are high, which makes sense given their location). I ordered the wrong cheese for C. and called to change it the night before delivery day and there was no charge to swap the cheeses, even tho the order had already been picked.
Delivery was to bell services at the Contemporary. When we checked in, we walked just to the right and gave them our room number; our groceries arrived shortly before our luggage arrived from Magical Express.
Disney Magical Express is a motorcoach service from MCO to resort hotels. There's a bathroom in the back; two seats on either side of the aisle. TVs scattered throughout supply some advertising for your upcoming (or, hopefully, future repeat) Disney vacation, depicting Disney characters riding the bus, on a Disney Cruise, checking into or out of hotels, eating at restaurants, blah blah bleeping blah. Not too obnoxious.
DME sends you luggage tags so you can check your bags through to your resort hotel. This is a Really Really Really Nice Feature. We had no trouble with it; bags arrive a little over an hour after we did. It does introduce an additional opportunity to lose bags; I have no idea what the overall risk is.
We had a flight delay on the way out, because our plane was late arriving at Logan. Also, the trip south was slower and longer than the trip north, which we believe to be because of prevailing winds.
Overall, JetBlue was a good experience. We've flown two visitors nonstop Seattle-Boston over the last few months; there were no significant issues altho some delays. We'll continue to use JetBlue. Disney Magical Express was a good experience, as was GardenGrocer.com. We will use these all again, and recommend them to others.