I got the RFE. I had changed company using AC21. USCIS wanted a letter from my current company describing my job title, job description and salary.
My attorney told me that USCIS is probably processing the cases before hand. But they will only approve it once the priority date becomes current. Nevertheless, its good to know that they are atleast working on the case.
We filed I-140 and I-485 in Fall 2004, so pretty close to Dec. 2004. I get used to be a pretty active participant of the forum before. Now, since we have already received our GCs in May 2007, I am not a frequent visitor of the forum any more. But I am very sympathetic to everyone who goes through this lengthy and difficult path, so I believe my information could be of use to you - at least as a successful statistics. Do not give up!