Errata: 

Theorem 1.2 claims O(1)-competitiveness. This is true. On page 16 though, there was a minor algebraic mistake: We claimed that the objective of DUAL_s is at least *1/2* of PF's total weighted completion time, which gives the conclusion that PF is *64*-competitive. The numbers should be corrected to *1/4* and *128* respectively.