On myopera, when contacts post things, it's unobtrusive. You get a little number at the top of the screen and visit the subscriptions whenever you like. Some of the other networks, like Google+, Diaspora, and Facebook, you get an initial stream, then you have to winnow it down from there. Heavy posters pollute the stream until nothing else can be seen but them.
Especially on Diaspora, I've found that after adding someone as a contact so that I can easily keep up with what they are posting, I find that the person is posting about 20 times an hour 24 hours a day. OMG! Go to bed sometimes. Who knows how they do it.
People can do whatever they want with their accounts. It's up to me to control what I want to see. I've just been overwhelmed and surprised quite a few times at the stamina of some people.