The new rumored thing about Second Life just turns out to be a another messenger. It mixes instant messages and the usage of voice, so you can remain online and reachable for all of your friends while not logged in using the normal, big fat client.
This has been a logical step in my opinion if you want to play in the field of big business and be reachable. There have been alternatives around, for quite some time, which play in the thin client business, like Ajaxlife or Slinked, but this is now the first one coming directly from Linden Lab and the only one which uses the voice capabilites of Second Life, too.
Well... how is this thing going to be adopted? I guess, it's use will be not going to be so widespread, since if people really wanted to have something like that, they could have already used existing thingies like Skype for a long time and they have done that.
So the audience of this is going to be people who want to stay in touch with Second Life while being at work or whereever and who are afraid to give out other contact possibilities. That's all.