Right now the G+ team is doing a lot of listening to the users and modifying the app in accordance as they go along, but make no mistake that the true purpose of the app is to copy all of Fb's functionality, clean it up and serve it to the user in the broader context of Google's ecosystem. I wouldn't be surprised if they launched a 140-character service next week.
Isn't Buzz their twitter-like product? Now Buzz has hardly been a success, but it would be interesting to see how they can integrate it with Google+ since it has such a different model for communication.
I am not using Buzz, so if I am wrong please correct me, but isn't it like this:
Google+ -> You opt in your followers to hear your broadcast.
Google Buzz/Twitter -> Your followers opt in to hear your broadcast.
I promptly forgot Buzz as soon as I heard about it, so I cannot speak intelligently about it. But I've been using G+ quiet frequently now for the past three weeks and it's in desperate need of Twitter-like functionality, and in its current incarnation it's simply not set up like that as you can only search for people and not content. Discovery vs. Cataloguing.
I'll cite as an example the POTUS appearance on the telly last night. As a live even it was all over Twitter, nary a mention on G+. And Facebook carried very little for me aside from announcing the event.
