I'm convinced they dumped most of that money into btc investments and are cashing out slowly and refunding people while making filthy amounts of money on the BTC growth over the last months. They will end up sending out a soso product after the first company or two beats them to the punch then will claim they still sent out what they promised performance wise which at this point I wouldn't trust.
What BTC investments? On the whole, BTC investments have had a pretty crappy track record this year. While it's possible that they converted customer payments to BTC and put everything in MtGox hoping to ride the exchange rate wave, it's not especially likely. Remember that Bitcoin prices weren't that great when ASIC pre-orders opened which is why so many people were investing in HYIPs. If BFL was converting pre-order revenue into BTC and placing it in HYIPs, I suspect that someone would have broken ranks and leaked that information by now.