Amy,
The SMF team (I believe I speak for all of us) would love to continue with Joomla, the day we saw them using SMF as their forum made us all smile, the fact they still do, is a compliment to the professional way they are acting.
Personally and as some of our team use joomla, would like to see things continue with them, its about biding time and finding new approaches.
I don't want to see bitter arguments, as there seems to be, legally, the bridge in its current state breaks the joomla license, therefore it was removed.
As for the mambo and other bridges that are online under GPL, we have searched there sites, forums, contacted people for many of the systems, and they seem happy with what we are doing, yes in the "Free Software Foundations" eyes we may be as illegal as movie pirates, however the fact remains, the FSF could shout and scream, and moan and whinge, but can't start a legal case against us, as it is not there software.
It's the same with us here Amy, we explicitly state we don't allow redistribution, however we make formal exceptions to certain people like Fantastico and a few other control panels, to allow them to use our software.