I guess I'm a little slow here, but what's the difference in Memory Maker and Photo Pass or are they the same thing?

I have always pre-purchased the Photo Pass and love it.
Photopass is the general name for the photo products. For example, I am a Photopass photographer because I take pictures for the system. You can buy individual products online or in person like prints, downloads, photobooks, etc.
Photopass+ (which I assuming you are talking about) was a product that you could pre-purchase or buy in the parks. You would collect photos with a red photopass card on a lanyard. Photopass+ would include all normal photos from the park, attraction photos, digital copies of resort/dining photos, and a print of the resort/dining photos. At the end of your trip you would edit your photos and then get mailed a CD/DVD of everything. You also got the gallery CD of the stock photos taken around the park. That product no longer exists, although it is honored if you pre-purchased it in advance.
Memory Maker replaces Photopass+ and is essentially the same thing. You get a white card with Mr. or Mrs. Incredible on it. You can also link it to your magic band if you are a resort guest or if you buy one in the parks. The big differences between the two are:
1. You no longer get the physically printed package at the resort/dining restaurants.
2. You no longer get the gallery disk.
3. Instead of a CD, you can download all the photos to your computer when you are done.
Besides that, they are the same.
I do get guests who ask me ALL the time if I am "One of those memory maker people" or "Do you take memory maker pictures." My favorite comment, as they approach me for the photos is, "Oh, by the way, we have memory maker." The answers to those are "Yes, although I am a human not a product," "Yes, everyone, literally anyone with a camera at Disney, does," and "That's nice, but I don't really need to know that."
I don't really say that by the way.