I'm not sure if they're actually selling new ones, or just shipping preorders from 6 months ago. And the reason they took preorders was to get the capital to fund the production in the first place.

It does seem like it would be awfully tempting to delay those preorder deliveries a little bit and use the machines first.

Avalon prices their hardware in bitcoins, so the higher the exchange rate the higher the price: http://launch.avalon-asics.com/.

Currently the supply is limited to 3600 per day, so if they did take all their orders and 'premine' for a day, they could at a maximum make about a half a million dollars a day (at the current trading rate). Note that if they started selling half a million dollars a day worth of bitcoin, they'd see the prices drop to less than $10, making their daily profits to around 50k. At that point, it may be more profitable just to ship their product. If you did buy one of these ASIC miners, most people don't realize that as soon as customers get ahold of them, the difficulty is going to go way up, since the hard limit of 3600 coins would be reached earlier in the day if it didn't. So, if they had 1000 customers, the most each customer could get in a day would be 3.6 coins... which at today's rate is $468 per day. Not too bad, but what would it cost to get that kind of hashrate? If it's $10k, then you'd have to mine for 21 days nonstop just to have it pay for itself. That's assuming the difficulty level would stay the same, which it probably wouldn't since the other players (BFL, etc) would release their products, thus decreasing your daily haul. Also, if everyone who mined coins sold, you'd look at a depreciating value for the currency, so your 3.6 coins might only be worth half as much.

But Avalon has pre-sold them, presumibly to fund the development & construction. To keep the machines, they'd need investment money, which they might not have.

Yes. Luckily, Avalon has a philosophical committment to improving the bitcoin transaction network.

Other suppliers which haven't established this idea can be accused of receiving orders and just running them locally for a while before sending them out.