For my own stuff, I plan to immediately slap on a temporary blank "leader" in AviSynth, just so I can use the X0 Project timing. I can chop it off later, when I'm ready to author. If this is the only version with timecode, then I'm going to take advantage. It's easy enough to determine the frame or time offsets to any other version, and adjust accordingly. In fact, I'm sort of surprised and disappointed that we haven't already seen offsets between X0 and some of the other well-regarded projects (Moth3r, Citizen, etc.) published somewhere. I'll bet they turn up sometime.
I'm also wondering if we'll see "re-releases" of some versions with X0-synched timecode applied. I'd totally download timecoded 1-CD "workprint"-like versions, just so I could have an easy way to line them all up and be able to pick and choose between all the available audio tracks, knowing I can port them without a lot of goofing around.
I don't think we've begun to even fully imagine how the X0 timecode could aid in the preservation and fan-edit processes!