If we believed current orders is a constant then (at time of post)
Just for fun mind:-
5821 orders we know 185 (5821/185=31.4648) times this by total TH ordered so far (31.4648*30.2475=951.731538)
so If it was taken seriously would be just under 952TH. WOW LOL.
so 951.731538*0.1396983916718426=132861722.7048 difficulty (0.1396983916718426 is difficulty per Mhs)
A 1TH rig would get you 951/1800=0.5283333333333333BTC Per day
Baring in mind all deliveries would have to be instant LOL!
You are assuming that each and every order in the system was actually real and paid for.
I think it would be closer to about 3-5 times what is reported here since every person looking at BFL is most likely aware of this thread.
So, 3 times 30TH = 90TH. And, that is probably at absolute most, since most orders went in at the beginning (especially for the Mini rigs).
REPORTED Orders have trailed off significantly even though the order numbers have increased.
I'm in complete agreement with you - at this point projections based on what we know are purely conjecture, but there's several points that aid in grounding.
First off we know that not every order goes through successfully (this being noted by several in this post already).
Next, the point about people making purchases being aware of this thread is highly likely, leaving three reasons for not posting (1) Apathy, (2) Desire to be anonymous, (3) Waiting to hit 5 hour mark so they can post. For the majority making a rig purchase, they're probably more likely than not forum members for a while ( assume if they are making ~30k purchase they have some interest in bitcointalk) so that places them in either category 1 or 2. Most purchases un-reported I think are likely singles or jalapeños at low volume who are newer members (including myself).
Finally, I think that there's several who are interested but don't go through with the purchase (even when the order is working correctly), just because they're unsure about going through with the transaction until there's a solid delivery.
Ultimately, I believe BFL will deliver (otherwise I wouldn't have made an order), and they're ramping up for much higher volume on this product line. But I think we won't see difficulty get to a point where mining isn't viable or profitable on ASICs in the next year - as of now ASICs aren't "off-the-shelf" mining equipment, there's a large number of potential customers waiting on a delivery before orders are being made. The difficulty will increase, I just don't think to that degree within the year - if it does mining will decrease until it becomes financially lucrative for most miners, either way interesting times ahead!