I have seen the official advisory to CMs as well as the list of questions/answers to prep CMs for guests reactions (it's quite lengthy - 15 questions - most advisories only have 3 or 4 Q/A).

This test will begin on May 1.

Jim hill (yes, that Jim Hill) and Stitch Kingdom say Disney will select people via email (I'm assuming those who are booked to vacation during May 1 - May 15th) to test out the xPass/NextGen system... you'll be able to plan every minute of your itinerary and will receive a FP/xPass card...
This isn't exactly the way I read the advisory. The way I read it, guests have probably been identified as possibile participants and will be asked if they'd like to participate upon their arrival. Email only comes into the picture because Disney will be sending an email confirmation to the guest (but the guest does not need to have access to email while at Disney). When the guest registers for the trial, it appears they get to select the attractions and time frame they'd prefer. They will then be issued a FastPass card (which has an RFID chip). The confirmation email will notify the guest of the attractions and FastPass return times that have been assigned. This information can also be obtained by using the FastPass card at one of the new FastPass machines or from City Hall.

It doesn't appear that any of the existing FastPass rules change - just the medium of the FastPass itself and the method of distributing them. And, of course, the method of letting you into the FastPass line.

To me, and granted the only info I have is from the CM advisory, it seems like they're testing the RFID technology to determine the feasibility of using it to replace (augment?) the paper FastPass system. It doesn't sound like the idea is to have guests plan every minute of their trip 180 days out.

Personally, I think I'd enjoy being able to get to a park, go up to a kiosk, select 3 or 4attractions and rough time frames I'd like and receive a card with those FastPasses on it. Even better if I can do this at my resort before I even get to the park. The only real difference between that and the existing system is the medium (plastic vs. paper) and not having to go to each location to get a FastPass.

While Disney has done some pretty stupid things lately IMHO, I'm going to remain optimistic on this one that Disney will maintain the overall structure, rules and limits of the FastPass system, as they attempt to give guests a better experience.

And BTW, the advisory says more than once:

We often test systems or technologies in our parks as part of our ongoing innovation process to make the entire Guest experience even better. The actual configuration we are testing may or may not end up in our parks.

Steve