It's basically given out the same as at WDW. How exactly it works may be a little different because WDW is newer than DL (except for California Adventure, which is newer and mostly accessible).
You can click on the link in my signature to get to the disABILITIES FAQs thread. Post #6 about Guest Assistance Cards and the general information in that thread is the same at both WDW and DL. There is also a post in that thread about DL (not a lot of information since we don't have as many posters on the disABILITIES Board who go to DL.