Thanks for the responses everyone!
shirtless' post actually raises an interesting point.
Consider two applicants. Both have everything else equal except the stuff mentioned below.
Applicant A: 3.85 GPA + 36 MCAT + mid-author in Nature/Cell/Science paper
Applicant B: 3.85 GPA 37 MCAT
Both have the same LizzyM
score after the 1 point boost from the paper for applicant A. Who is the more impressive applicant? If you think it is applicant A, then the paper would be more than 1 LizzyM point.
Nonetheless, I think it would depend on who is viewing the application. Perhaps at some schools (maybe LizzyM's school) publications are not as favored as much as they are at some other schools.