In terms of Sober's selection of/selection for distinction, is it appropriate to say that there was selection of or selection for an allele that evolved by hitchhiking? I am inclined to say selection of. Is that correct?
The expressions "selection for" and "selection of", their definitions and their usage have been subject to a number of semantic issues throughout the literature. Good and Griffith (1995) is a good read on the subject.
I would argue that neither "selection for" or "selection of" is appropriate to use in the context of genetic hitchhiking because, in this context, by definition, the increase in frequency of an allele is only due to a different locus nearby that is under selection. So an allele that evolves due to hitchhiking is not directly under selection and only changes frequency indirectly due to nearby selection on a linked site.