I love Google+. I have been trying it out for the past week. Lots of fun, easy to use. There is a ton of great potential here.

But is it a Facebook killer? Or even a Twitter killer?

The content I have seen people share on Google+ is in many ways similar to what I see on Facebook. Lots of fun videos, pictures, some status updates. The discussion and article sharing that does go on tends to be about Google+ itself. That makes sense: people are still figuring out how Google+ works. My guess is this will changes as people use it more.

However, while I love the theory of how Circles could work with Google+, I think in practice it could get messy. Twitter will likely still be the best place to broadcast and share news, at least with the way Circles work now.

With Google+, each of your connections needs to be put into at least one Circle, which are sort of a hybrid between Twitter lists and Facebook friend lists. You can use Circles to filter the Stream of posts you see from others to focus on seeing what is being shared by just a certain subset of your friends or colleagues or whatever. You can also use Circles to broadcast what you share to just a certain subset of your contacts.

That’s where things get pretty complex.

Let’s just say that in theory that everybody on Google+ shared everything with Public. In that case, people who had put you into a Circle would see your post in their home Stream as well as in the stream for the Circle or Circles they had put you in. Also, anybody who took a look at your profile could see your post as well. In this case, Google+ would work very similar to Twitter, at least in terms of how sharing works. If you find somebody you think is interesting, you could circle them and then see the content they are sharing with the hope that it will be useful to you.

However, what happens if you decide to share content only with people in your Circles? In that case, people may have put you in a Circle, but unless you have reciprocated, they will not see your content. If you shared to Extended Circles, then if you have circled person A and person A circled person B, then person B will see your content. Either way, if somebody outside your Circles or Extended Circles visits your profile, they will not see your post. This is perhaps fine if you are sharing a picture of your puppy, but probably not so much if you are trying to share a blog post far and wide. Still, as long as you are clear on what you want public or not, Public vs Circles is a useful distinction.

The messy part is when you start sharing to a particular Circle or even a group of Circles. In that case, people will only see your content if they have circled you and you have circled them and properly classified them as part of the Circle to which you are sharing that content. They will see this content in their home Stream as well as in the stream of any Circles in which you appear. Again, if you are sharing content only relevant to, say, your family, this should work fairly well.

Let’s just say that in theory you were able to get all your friends from Facebook to sign up for Google+ and the same was true of all the people you follow on Twitter and all the people who follow you. Maybe a stretch, but I am just theorizing here.

On Twitter, I share a lot of content about web design, particularly about Drupal and accessibility and web standards. As well, I share Mac news I find interesting, as well other odds and ends, such as fun Star Wars stuff. The people who follow me might not find all those topics interesting, but hopefully they find enough of them interesting that they stick around.

On Facebook, I share more random tidbits of life and fun content like interesting videos as well as a few thoughts on things like politics that I would probably be less likely to share on Twitter.

Would my friends from high school really be interested in every article I share about responsive web design? If they aren’t, they could certainly put me in a Circle of People Who Gab On and On About Things I Don't Care About. But if they are looking at their home Stream, they will still see my content. Maybe they create a circle of People Who Actually Share Things That Are Interesting and primarily follow that. But if they do, then if I do share something relevant, they will not see it.

So let’s say I don’t want to bother all my contacts with articles about accessible web design. So I share that content with just the people in my accessibility circle. Or even a Circle that contains everyone I think might be interested in web design. However, the only people who will see that content are those who have circled me, and who are looking at their home Stream or a Circle with me in it. If people are interested in my web design content, but I have not yet circled them? They are out of luck. Or if I did not really know who they were and put them in a People I Don't Know Circle, again, out of luck.

What could help this is, in theory, would be tagging content. For example, you could say on your profile: I share content from these five tags, and I am interested in content from these ten tags. Person A is tagged as being interested in Web Design content. Person B is tagged as being interested in Star Wars content. Now I know exactly what circles to put them in. Person A could set up a Circle that would have only content shared as Web Design. Person B has a Circle for content tagged with Star Wars. Now person B can see my Star Wars content without having to worry about getting the Web Design content that is not as interesting for him or her.

However, Circles are complicated enough: tagging would be even trickier. And how do you maintain a master list of tags that isn’t completely overwhelming while allowing people to accurately tag their content? And doesn’t this contribute to the problem of people getting stuck in filter bubbles?

Again, if everybody shares interesting content to Public, few of these problems show up. But if people start using Circles to share topic-based content, I think Twitter will have some advantages in terms of being able to consistently share and receive content.

I may be wrong on this, though. Things may change and different behaviors may emerge. Your thoughts and comments are welcome!