Orca Firefox 3 better accessible?

[Hermann <steppenwolf2 onlinehome de>]

Hi,
I downloaded and tested FF 3, aka Granparadiso.
The released alpha version crashes every 5 minutes, and the quality 
feedback assistant is not accessible; so there was no testin.
I then downloaded a nightly build of FF 3, and this works stable on my 
machine.
However: What is the diference regarding accessibility between FF 2.0 an 3?
I heard that websites that are not designed under the standards of w3c are 
better accessible, which is indeed a progress. But I'll put the emphasis on 
the handling of webpages for the user. Is there a better reading and 
navigating of the sites, I think no.
One difference I could figure out is that the letter "h" moves to the next 
heading and shift+h moves backward. But: If you press alt+h to access the 
help menu, you get read the next heading; you've to search for the menu bar 
and click "help".
In my case there's even a slight regress, because I cannot use FireVox with 
FF 3; on new versions no extention works.
To explain: FireVox is an extention written by Charles Chen, which provides 
some useful additional reading and navigation commands for FF until version 
2.0. This extention makes FF more handy for blind and visually impaired 
users. The URL is:
http://firevox.clcworld.net
What's your experience with FF 3 and Orca?
Regards
Hermann