Just came across this article on CoinDesk, figured I'd share it: http://www.coindesk.com/inside-butterfly-labs-the-challenges-of-producing-bitcoin-mining-hardware/
They claim to be shipping 300 units a day; the fact that very very few of you have been receiving yours makes that possibility a little scary... They're shipping orders in the order in which they were received, but even if they were only shipping 5 GH/s units, that's 1.5 TH/s a day being added to the network; 45 TH/s a month. Scary stuff!
you still didnt count all other ASIC devices and USB miners, so we should see more than 100TH (just guess no numbers or math) added each month... This is not going to happen this month probably
and also you were just counting with 5GH/s units, they can ship 300 60GH/s units each day (18TH/day)*30=540TH/s each month :D