Availability of PowerPC hardware suitable for operation with Amiga OS 4.0 will be announced by third parties early 2007.
A prototype of the
SAM440EP (codenamed: Samantha) was shown at an Amiga show a few months ago.
Text from their website:
"Availability
Within the first quarter of 2007"
I'm not confident of them achieving that release date, but I believe this will be the first "post-A1" OS4 platform to make it to the market.