Shane: (I haven't figured out how to quote individual snippets XD) In regards to a second-level tiebreak if both games take the same number of moves (unlikely), we could go by which player ended up with more material on the board (1 point for each pawn, 3 per knight and bishop, 5 per rook, 9 per queen), and after that we could go by whose king advanced further.  I doubt we'll need more than three levels of tiebreakers.   

Aye.
Still, better safe than sorry.

In regards to the limit of twenty-four hours (or any other number): Maybe we could allow a player to declare in advance that he won't be moving within the time limit, say if he's going camping and won't have Internet access.

I agree.

And if something unexpected happens, such as, say, a power outage, and a player doesn't have any other way of notifying us...?

That would be unexpected... and a problem, I'd say...