I love the script... I have a suggestion (and a neat tip) that I'd love to see integrated, but I'm not totally up on the dbus stuff enough to do it. Maybe you are?

One interesting feature/hack for texting groups of people is that you can use the "Nickname" field to group people together. If you gave 5 people the nickname "GroupA", for example, then type GroupA into the To: field for a new SMS and hit the To: button, it lists those 5 people for quick selection. I use this already for texting groups of friends.

I would love if this script could (instead of making it's own mini database) use calls to ask the address book for people with a Nickname containing "GroupA" to setup the ring tone (and/or text tone?). That would make grouping a lot more integrated.

I'm hopeful that someone will make an extension (like the IM extensions) that adds a "Group" field to the address book that everyone can key off of, instead of (ab)using the Nickname field.