Amiga Inc has posted a AA2 FAQ on their page.
http://www.amiga.com/faqs/
Q: I have heard about something called "OS5". Is this the same thing?
A: No. AA2 and the product often referred to as OS5 are entirely separate distinct products.
Q: So what is OS5 then?
A: OS5 is an ongoing project to build a new distributed virtualized operating system (in the true sense of the term operating system) that is also capable of running in a hosted form. OS5 is a long-term project that incorporates many of the next generation operating system concepts Amiga has extolled in the past.
There are a few more AA2 vs OS5 answers there.
Nothing really new. Except they continue to refute that AA2 = OS5.
Good news, if they will deliver...
EDIT/OFF TOPIC:They've had one press release a month in 2008, that is a 42% increase since 2007 if they keep it up.
A sign of increased activity?