After spending countless hours on Google+, I have realized how useful their new group feature is, for sharing/finding interesting stuff happening around different technologies. It's nice handling of previews of movies, images, webpages etc makes it so much easier to spot interesting stuff. IMO it works FAR better than e.g. twitter, for this.
E.g. by subscribing to groups for the topics you are interested in (I have over 50...), I get tons of interesting stuff on your Google+ home page all the time.
While Google+ groups definitely don't replace mailing lists and IRC, which are superior for discussions, it is a great complement for sharing interesting stuff happening around a technology.
With this in mind, during the last week or so, I've tried to make sure that a few of my favourite softwares and topics have groups, which resulted in a few new ones:
... so make sure to join those of these that you like, and post some interesting stuff there! :)