Google Plus Limits

I posted an item today that reached what is apparently the maximum number of possible shares on Google+: 1,000 shares!

https://plus.google.com/113117251731252114390/posts/aQYKVc5GPVK

So now we know the max on comments is 500 and max shares is 1,000. 

The max number of users you can Circle is 5,000, and the max number in any one Circle is also 5,000. 

Is there a maximum number of people who can Circle a person?

Is there a max on +1s? 

Is there a max character count for posts? via Mike Elgan