Don't sweat about it. My RD is Sep 21 and I also haven't got any FP letter. Our DO is also SJ. I have seen from other forums and threads that sometimes in SJ, you get IL first and then FP letter. justindian_03 in July/Aug thread got his FP letter almost 2 weeks after IL. HIs RD was Aug 23 and IV Is in Dec while FP is I think in Nov.
Anyways, FP is required before I-485 approval but FP Check clearance are usually returned in a day or two, so even if you have FP 1-2 days before your interview, there are chances you get I-485 approved during your IV. The only scary part is name check. Hope no one gets caught in that issue as it has no end dates.
For a moment I thought you had abandoned us. Am glad we are all still holding on. Definitely we shall all have your GC before 12/31/2007.