Signed 648 (ship.2 release candidate)

[Yoshiki Ohshima]

> A signed copy of build 648, which is our ship.2 release candidate, is now at:
>      http://download.laptop.org/xo-1/os/official/648/jffs2/
> This build contains firmware q2d05, available separately at:
>     http://dev.laptop.org/pub/firmware/q2d05/

  Great!  but sorry for my ignorance but what "a signed copy" means?
Shall we test it on our (B4) laptops?  Or it'll make it hard for
future update? 

http://xs-dev.laptop.org/~cscott/olpc/streams/ship.2/build648/devel_jffs2/

is the same thing but "unsigned"?

-- Yoshiki