Well, by my calendar, today is the end of the 1st quarter of 2006, and FP's are still free to all. If they weren't free next quarter, you'd think they would have announced something to this effect. That gets us to the middle of summer. If they start charging non-resort guests for FP's in the middle of summer without more notice than this, there will be a lot of backlash, IMO.
Until I see something in writing about it from WDW, I don't put much stock in anything else. Anything else, to me, is pure speculation.
For the record: I strongly oppose such a park perk for resort guests. Offsite guests pay just as much to get into the parks as onsite guests. Resort guests already get enough park perks as it is, and this would just be an over-reach on Disney's part, IMHO. Rather than encouraging guests to stay in their resorts, I think it could have the opposite effect of driving guests away from WDW entirely.
Once you give something to someone for free, and then take it away or make them pay for it, the reaction to it would be much worse than if you never gave a freebie to someone in the first place. Well, that sounds convoluted, but I hope all get my meaning.
Anyway, it's still just speculation.