I'm not the only one who has been agitated by the whole mystery of the approval process either. There are numerous complaints on the developer forums of the bad service, with horror stories of apps being rejected after excruciatingly long wait times (and for blatantly obvious nit-picks, which you'd think would have been punted back to the developer almost immediately).
I've noticed a trend as of late, too: similarly themed apps all appear on the App Store in the exact same timeframe. Recently there was a rash of fake geiger counter apps. I fear that my app is being unjustly held up so that it can be released with other people who had the exact same idea. Of course I have no idea if that's true or not. Only time will tell. Three weeks and counting.............