Access to the network is filtering out slowly from the social circle of Google employees, so at the moment G+ has fairly nerdy content. There is also a lot of excitement amongst these early adopters and some people are saying they will delete their Facebook accounts and never go back because G+ is so much better. I agree it's better but I'd like to argue for a cool down period before people start drawing lines in the sand and pressuring others to switch.
I think you should think of social networks as if they were cities.
There are a lot of these cities and towns right now all with very different cultures and populations:
Many people 'live' in multiple cities and this is as it should be since they all offer quite different experiences. The thing with G+ is that it is more general than most of these services and in particular it seems that the goal is that very soon more features will be added so that G+ will completely subsume the features of Facebook and Twitter. So, you know, it is war in fact.
But keep in mind it is war between the companies running these services, the populations don't need to get involved.
We probably all have a home city, a social network we live in more than others. For most people that's Facebook. It's like the suburban heartland megacity of social networks. Its pretty much where everyone is, its good, could be better, it's full of drive-thrus fast food, highways and casinos; but it's hard to change things now because its so damn big.
For other people their home is Twitter.
Twitter is so cool you don't even need to talk, you just exchange compact, knowing glances and handshakes. Its Seattle, Montreal or the Village; it doesn't need you and your paragraph length diatribes.
But now we have G+. It's cool, technically savvy, fast and connects everything. It's San Francisco and all the nerds are moving over and proclaiming in their old haunts how much better everything would be if all your pleebs just switched over too.
Just because you move to a new city and like it better doesn't mean you abandon the old one entirely. You still know alot of people in the old place, people you care about, one would assume. Hassling those people to come live in your fancy new city, even saying you're just not going to call or visit the old place because it so out of date, well, that's kind of rude. You wouldn't threaten to cut all contact with people just because they refuse to move to another city in the real world, so why do it in the virtual world? (I know its not exactly the same, since you probably will still email or meet these people in real life, but there is a personal tone developing to the community you use which seems unnecessary)
Some people just don't like moving and may never move. When it comes down to it, these social network cities are about the people in them, not the technology we are using. So I'm still in FacebookCity and I'm going to stay, or at least keep visiting, as long as I have lots of friends there, which will be for a long time I expet.
But lets just say I'm not buying a new house there anytime soon and I'm spending a lot of time visiting the shiny new metropolis. So if you want to stop by, I'll show you around.