Update 07/28/14 - I spoke with folks in McCall, and the Twentymile Trail has been fully cleared in the past few day by moto riders and volunteers. Trail crews are working on Bear Pete right now.
This does not mean there will not be more trees that fall in the future. Even during this riding season.
As stated on the maps, I cannot emphasize enough that all of the Singletrack Options are true backcountry epics. They are extremely difficult, and riders need to plan for encountering obstacles such as downed trees, rutted out trails, long hike-a-bikes, and moving water crossings. If those situations are in any way unappealing, I recommend not attempting any of the Singletrack Options.
The reality is, none of the Singletrack Options will ever be 100% rideable.