Couple of differences, actually.
First of all, Disneyland's PeopleMover was sponsored by Goodyear, so the vehicles were actually operated by perpetually-spinning Goodyear tires embedded into the track. Each spinning tire would push each vehicle down the track over to the next tire, etc. For WDW, the Imagineers developed a new system based on electric induction, a technology they named the WEDway, leading to the attraction's popular name, WEDway Peoplemover.
The speeds were also pretty different. WDW's Peoplemover changes speeds drastically throughout the ride - often brisk enough to run a breeze through your hair, and occasionally slow enough that you can admire Epcot models or gift shop interiors. Disneyland's was consistently very slow for the whole ride, leading to the opinion by some that the ride was more boring than the WDW version. This is something I hope they address should the ride ever come.
Also, and this may be common knowledge, the Disneyland ride featured an open-air track, with each vehicle individually covered, while in WDW the vehicles are open and the track is covered.
Part of the reason Disneyland's ride is closed is because many of the interior parts of the ride have walls that are too close to the vehicle, so that (in theory) guests could reach out and injure themselves while the vehicle was in motion. From what I understand, Disney is currently in the very difficult process of finding a way to correct this, which could require either restraining guests somehow, or embarking in the costly process of pushing out the walls.
WDW apparently either circumvents this through grandfather clauses, or the attraction was built in a way which meets modern code.
No way!
I can pretty much guarantee that the Rocket Rods, in their previous form, will never come back. The damage that attraction did to those tracks is something Disney never want to have on their hands again.
