I am now firmly of the belief that links are no longer the metric of choice for google.
Prior to my noticing that "nothing" is working - I did notice that the things which had been working tended to fizzle out once a site reached the top 10. This was irrespective of competition levels.
Im going to make a bit of a guess here - sorry a bold guess - but I think that google has incorporated the AGE of "THINGS" into the algo more now - and I think this far far far outweighs new links.
I fear the age of a link is of paramount importance - moreso than the trust / PR / whatever reputation of the link giving site.
I will be driving past Mcdonalds later and popping my head in there to get that job before you lot get there before me.