Proto:WWF SmackDown!

Title Screen
The first obvious difference is the title screen. It is different than the final versions and it has the build date printed on the upper left corner (January 6, 2000 6:05:29)

Selection Pictures
The selection screen pictures of the wrestlers almost look like mugshots.

Wrestler Differences
Chyna's skin color is dark in the prototype, it's white in the final

Gameplay
There is no interaction with the scenery when you are backstage (Final version had some)

There is some weapons that are not in the final version of the game, most notably a table (not breakable sadly), steel steps, casket (looks like the one used SD2)

Attacks with small weapons like the microphone do not register as hits, but running attacks work with them

Debug Features
When you actually play a match, under the health bars are 2-4 lines of debug code (changes depending on how many wrestlers are in a match) that cannot be turned off.

Bits of debug code appear in the top left corner during cutscenes in season mode, pressing L1 and L2 bring up more debug code and bars

Season Mode
At the screen where it shows the date and which show is next there is a list of wrestlers with numbers next to their name, pressing R2 and L2 changes the wrestlers in that list, pressing circle brings up another list with wrestlers and numbers which you can scroll through by pressing up/down, #29 just has the name 'XXX' (a removed wrestler?). Holding square makes said text dissapear

After that screen sometimes it will show a black screen with some debug code (maybe for cutscenes)

There is no warning when skipping your match in season mode, and when you skip a match it doesnt automatically go onto the next one meaning it is easy to skip your match by accident

Pressing square at the season mode menu plays back the last cutscene that happened (although not always with the same people)

Some cutscenes are unfinished text-wise and some crash the game before loading

The camera can actually be controlled during cutscenes using the second controller by either pressing start or select on it

Create A Wrestler
Pressing select at the first menu brings up abit of debug code and a bar

When changing the appearance of your created wrestler there is 2 rows and 4 columns of debug code in the top left corner, 7 rows for each different body part (head, upper body etc). one one set is for the camera angle. At the last edit screen where you change your height/weight etc there is another 2 sets of numbers that change with your height/weight

Some parts are missing (Removed wrestlers?)

Head: 36, 38-48, 61, 78 Upper Body: 36, 38,39 Lower Body: 44,45,46 When you are choosing your moves, Pressing L2 unlocks all of them. Pressing select changes the moves names to a bunch of numbers

Options Menu
You can access the majority of the options menu when you pause during a match. Also, while in the options menu, you can turn on and off the entrance videos, Dual Shock support, and auto save (though the last one might have been in the release copy, I'm not sure).

Engrish
It appears that this build is later than the one used by GameSpot for their screenshots, considering the infamous "3 Way Dancing" is replaced with the more sensible "3 Way Dance". It seems other things are mistranslated or mistyped, too, such as "Punphandle Slam" and "matchmakes".

Title Holders
In the retail release, the title holders are like this:

WWF Champion                 Triple H Intercontinental Champion     Chris Jericho European Champion            Val Venis Hardcore Champion            Big Boss Man Tag Team Champions           Road Dogg and Mr. Ass Women's Champion             Tori

However, in this prototype, the title holders are this:

WWF Champion                 Big Show Intercontinental Champion    Chris Jericho European Champion            Val Venis Hardcore Champion            Big Boss Man Tag Team Champions           The Rock and Mankind Women's Champion             Tori

Not much of a difference, but it shows you that they tried to be a little more current in the retail release.