You can also now do this from your computer (not just your smartphone), and do it just before you go to, or just after you return from your venue, not just while you're there.
The jury is still out on the new privacy stuff though.
I'm not saying plus will win the social wars because Facebook has a lot of people because it built up a lot of momentum. But if it looses it won't be because people found it too nerdy / geeky or whatever. It just means Facebook had a huge advantage and they didn't let it slip.
Except for the massive issues surrounding name use and the triviality in which it can be used to grief other people and not just on Google+ but their entire google account.
The somewhat technical explanation is that what Google is doing is implementing something very similar to "Social role theory" (http://en.wikipedia.org/wiki/Role_Theory), which emphasizes social roles as the defining characteristic used to understand social interaction. While Facebook rather is implementing something more akin to "Symbolic interaction theory" (http://en.wikipedia.org/wiki/Symbolic_interaction).
I think it's pretty obvious that Facebook has been, from the start, something very different. It is so ingrained in every little design decision and how they promote and talk about the service that it is a tool for managing your public persona. Not a simple communication tool, or replacement for email. Though they obviously offer that kind of functionality as well through Messages and Chat.
Facebook wants to enhance or maybe even change the way you interact socially. It's not a political agenda, but it is definitly a very conscious mission to change a large part of western culture.
There seems to be a lot of confusion about this. So let me state it again to make it clear:
FACEBOOK IS A TOOL FOR MANAGING YOUR PUBLIC PERSONA.
You are profoundly fooling yourself if you think that most Facebook users aren't using it as a way to CC a list of people some photos. I don't know anyone outside of the tech/blog scene who uses Facebook to manage a public persona. It's just a different way to communicate with people.
FACEBOOK IS A TOOL TO MAKE YOU (the user, their product) MORE MARKETABLE TO ADVERTISERS (the customers).
By knowing everything about you, they can get better rates from advertisers. Everything else, like photo sharing, and the ability to send messages to other people, or check into place, is designed to get more info about you, and to make sure you don't wander off Facebook to their competitors (if you didn't have picture sharing, you'd be using Picasa or Flicker more -- and that might threaten facebook).
Although I think google+ is a welcome player on the market what really frustrates me is that I am forced to add people to some circle.
Why forced?
The same reason LinkedIn "Completion Bar" is effective.
It taxes on your cognitive energy to see people not applied to a specific circle.
Twitters work much better where people just can follow me.
No tips, no explore, No trending, No badges (worthless, but fun), and less specials than Foursquare.
To be fair, I have many friends who use Foursquare for its most obvious and intended purpose, which is to arrange spontaneous meetups without having to text all their friends where they are or to find out where everybody is going. I do it myself, I just pop open 4sq on the phone and see "oh, everybody is at Foo's Bar" and then go there. Easy. Facebook Places makes that simple action incredibly difficult and slow.
Places essentially fails as well because it broadens the userbase too much. My college friends whom I no longer live near couldn't care less what bar I'm at. My local friends who I'm friends with on 4sq do care. So there's a natural separation. I'm only 4sq friends with people I'm likely to see often. I'm Facebook friends with almost everybody I've ever known.
Location as meta is a good thing for Facebook. Location as check-in doesn't fit with Facebook's friend model.
It's a bit like saying: "Oh, by the way. I might be hanging out down at the bar tonight. Swing by if you feel like it". Without actually having to say it out loud.
edit: The more I think about this, the more angry I get. It feels like the Google+ nerd mafia is slowly destroying Facebook through bad influence. They simply don't understand how and why Facebook works and is popular. The whole privacy and circles stuff for example, which is just stupid. No normal person cares about that. Facebook is a tool for sharing and connecting and to limit that in the name of privacy is insanely counterproductive. It only adds a wet blanket of politics on something that is better understood through social psychology and sociology. Facebook used to understand that, but now it seems they've started to become distracted. Sad really.