Jacky Mok just posted a link to the system requirements for the soon to be released Windows Live Suite apps, and they include 64bit support, but only if you’re running Vista.  from Jacky’s blog post:

Platform	32 bits	64 bits
XP SP2	Yes	No
Vista	Yes	Yes
Vista SP1	Yes	Yes
2003 Server	No	No

 

32 Bit Includes:  Mail, Messenger, Photo Gallery, Sign-in Assistant, Toolbar, Writer, Family Safety,
64 Bit Includes:  Mail, Messenger, Photo Gallery, Sign-in Assistant, Toolbar, Writer

The installer should auto detect the architecture and omit Family Safety if you are on 64 bits.

In addition Jacky is hinting pretty broadly, as we posted, that @live.xx addresses should be available very very soon.  He also says “I also suggest you to stay close to my blog today….“.  Oh we will, Jacky, we will.