I have circled many people whose posts I never want to miss. To make sure I get to read all they write, I have created a few Notification Circles. Many profiles are in several circles and I should perhaps clean them up, but as the final maximum I can have in my circles or 5000 is not affected by these "double appearances", I haven't bothered. The main thing is to gather all the most interesting peeps or Pages in one or two circles, "with bells on"!
To control the volume of each of your circles you can go to your Home page and then click open each of the circles listed in the More drop down:
Choose how much you can see from each circle in your Home stream:
The bell is for notifications, if you click it on, every post from the circle will send you a notification.
Unchecking the "Show posts in Home stream" mutes the circle - no posts shown.
Now Google has made subscribing to circles easier
There is a new page where all your circles are displayed and you can subscribe to some or all of them.
Word of warning!
Do not subscribe to all of them, as each post will create a notification under +Mr. Jingles and perhaps also send an email, depending on your settings. You will very soon be inundated in notifications!
To undo the subscription you can either visit each circle individually and click on the bell or just visit the subscription page and click the red "Notifications on" again to unsubscribe.
I recommend you choose carefully the people you place in a subscription circle. Keep it small.
If you haven't yet been shown this page when logging in to Google+, follow this link to get to the subscription page! Or log out and log back in. The feature is rolling out slowly.
I don't know if this is a glitch on this page or meant: When you are hovering over a thumbnail image of a profile, there is no way to change circles from the hovercard like it normally is. The checkboxes are missing. Only happens on this page.
I hope this new feature page means that we are one step closer to being able to control all our circle volumes in one place... Pretty please, Google?
More about Google+ Circles
Having trouble adding people to circles?
Allow your Circles to Hangout with you
Circloscope circle management tool
This post is really not relevant, but I wanted you to read it anyway! :-)