OK guys, now I am allowed to bring out the "big news" about the flash contents of the ACA500: It's Kickstart ROM images!
The ACA500 will be delivered with two Kickstart licenses: V1.3 and V3.1. This will let (almost) all A500's out there run the most important software: Some games/demos require Kick1.3 to work, and for WB-based programs, Kick3.1 is the first choice.
The word "almost" has to be explained: the flash chip on the ACA500 is only 512k, and that' not enough to hold both Kickstart images. Only Kick3.1 is in there as crunched image, and Kick1.3 is stored as a "diff" from 1.2 to 1.3. This gives you the following choices:
With physical 1.2 ROM: V1.2/V1.3/V3.1
With physical 1.3 ROM: V1.3/V3.1
With physical 2.0 ROM: V2.0/V3.1
With physical 3.1 ROM: no choice, just Kick 3.1.
This doesn't mean a disadvantage, because you can still load a Kickstart image from CF, so the small size of the flash chip on the ACA500 and the physically installed ROM chip don't actually make a difference.
In addition to that, the FAT95 filesystem will be in the ACA500's flash, so you can use a PC-formatted CF card "out of the box". If that wasn't in the flash, the user would have the task to transfer data (the filesystem) into the A500 before he can use the transfer-method "CF-card". This is a classic chicken-and-egg problem, and the pre-installed filesystem and automatic mounter can break the circle of "you need to transfer data in order to install the transfer method". It will just work without an error-prone installation procedure.
Also check the news on the Hyperion site and my website (does anyone want to make this a separate news item in this forum?)