One problem I think we may have, whether creating a separate list or prefixing posts with [JOB], is that less-frequent posters/list viewers [like myself] would not be aware of the separate list or the subject prefix requested...so the group is likely to keep getting them regardless. Certainly, with time, more and more people would catch on, and the volume of such postings would likely decrease (and perhaps that's good enough), but I think it'd still continue.
Do any of the other local user group lists break job requests out? Why (or why not)? We might be able to learn from how some of the other group have handled this.
I've posted a few contract or job requests to the board, and I'm all for handling those however the group collectively would like them to be handled, but I only noticed this post because I happened to see that JT (my friend & business partner) had posted to it. Had he not, I may have overlooked this, and posted again in the future without knowing the "proper protocol". It'd be interesting to take a straw poll and see how many of the people who have recently posted jobs to the group saw this...maybe most of the job postings are regulars who would see it...but maybe not.
Anyway, that's just my $.02 worth...