superpages?

[Wojciech Puchar]

maybe not new news but i just found this:

http://www.h-online.com/open/FreeBSD-7-2-released-now-with-Superpages--/news/113204

It says about pages 4KB and 4MB and that it's done 
automatically.

Two questions:

1) is it on all architectures including amd64? As amd64 supports 4KB, 2MB 
and 1GB pages it sounds inconsistent with the above.

2) how does this "automatic" selection work. By just having program with 
large continous data space (like squid proxy) will it put that data on 2MB 
pages.

if it's true i would be enough reason to upgrade to 7.2 on 2 computers.

thanks