Thinking about the new-product-introduction process... There are prototype hardware and alpha software delivered from the contract manufacturer (which may even be overseas). This was likely the hardware/software that Curt showed at the trade show last month. There may have been some critical bugs that would have frozen the system but you can bet Curt would not have ventured into any of the areas with known problems during the show.
At some point, Curt is happy with the hardware design and he gives the go-decision to the production builds. They need to make their way to the Neptune warehouse (which may be Curt's bedroom for all I know

).
I'm guessing that pre-order and delivery targets are set based on hardware stability.
Since then there may have been software bugs uncovered (see the ACiii firmware update thread) that need to be fixed.
Again, at some point Curt is happy and decides to re-flash all of his first-run production units that were already on the boat.
When he is ready, he will announce pre-orders and ship as soon as possible.
Holding him to any communication plan is just not feasible based on the number of variables in the air. I personally hope that they are shipped soon as I am currently without a controller. I'd like to think he is busy re-flashing them now and ready to enable the new part umbers and pricing on the purchasing site.
Anyway, saying that this is a hush-hush attitude and saying that any more delays in communications would force other choices is just silly to me. Yes, pre-orders were not opened in the first week of May, but that means little if there were no expectations for delivery until the end of May anyway. Why send money any sooner than you have to? You are free to make other choices, go for it if you want.