I was just there April 1-5 with my DS-7 w/autism, and it was the same situation as usual when it came to getting the GAC. We got it @ MK, and kept it in a plastic pouch I brought from home. They do check it over at each ride for the dates valid, and the number in our party. One time a CM at AK even asked me for my name and then checked the card...not sure why that was the case there.
Last time we went in September and lines (one of his issues) were very short so we did not use the GAC a lot. This time lines were LONG (100 + minutes for Test Track, Soarin', Splash Mtn, Space Mtn to name a few) so we did use it more often.
We each wore Autism Awareness pins this time, which helped some people understand our situation- you had to know what the icon meant though... Still got more stares, etc than needed at Aladdin and Dumbo due to the fact that you load there in the handicap area but I am getting better at handling that.
The only thing different this time was a few times on BTMR we were directed to the handicap entrance instead of FastPass...not sure why... Other times we did the FastPass line with about a 10 minute wait, which was no problem. The first time we were sent to the handicap entrance (early in day, 10 am) with very little wait; the second time, which was late in the day (7 pm) we waited a while in the handicap line-not sure why we were sent there and not FP line- CM helping us was confused too.
DS frightened to pieces of HM and won't even go near it, so we did not try that so I can't speak to that. Big advances this trip for us were going on Spaceship Earth, Space Mountain, Splash Mountain and Kali River Rapids for the first time and loving it!