The next updates on my Quake 3 lineup will mostly be quality of life updates. (almost) all ports will get their release on the same day.
But to put it shortly:
Wii will have a slight memory optimization and will have its graphics improved thanks to it.
PS3, WiiU. More specifically Quake 3, Team Arena and Open Arena will run better with bots since qagame will be native from now on.
PS4 will have access to more memory while also supporting gyro controls using Dualshock 4.