So, why is it the consensus opinion of this list that the Ataru & Lum
match is inevitable but the Ranma & Shampoo match is highly unlikely?

Because Ataru actually loves Lum?  Because, as Kun-chan said, Ranma
wouldn't save Shampoo if he could save Akane, and Ataru would probably
not save his other "girls" if he could save Lum.  (Actually, Ataru would
probably figure out a way that they wouldn't be in danger in the first
place.  I've been reading more UY lately, and feel that, especially
towards the end of the series, Ataru's intelligence is dangerously
underestimated.)  Remember, Shampoo was Rumiko's attempt at doing Lum
correctly.  IMO, it worked:  Shampoo is far more annoying than Lum.

--Sean Gaffney
--ducking...