But there are other practices that may seem quite benign that can get you categorized in the same way. You have to be careful of these because you could wind up being suspended or even banned simply because you were being overly enthusiastic.
Take posting links to multiple groups and communities. A lot of bloggers do this with their latest blog posts. Many would say that doing this is inherently a bit spammy. I'd have to agree. But I suppose the extent to which it can be seen as such it depends on how much you've engaged with the other community members first.
If it's the only thing you've ever done in the groups in question, then yes, it's spam pure and simple. But it's not so bad if you've been an active participant in other ways beforehand. And it can get a few clicks coming in that you wouldn't have gotten otherwise. So bloggers keep doing it.
Google Plus different to other networks
And each social network seems to have a different take on it. If you drop your links on many Facebook groups in quick succession there doesn't seem to be any internal flag you're raising -- at least not one that might have ramifications for your account status. But if you do that on Google Plus the internal algorithm will automatically mark the posts as spam. So obviously you want to avoid doing this on the site.
The other thing that occurs when you do this is that all those identical posts to Google Plus communities will appear on your public profile. That makes you look desperate and spammy to people who have found your profile and are considering circling you. And that may well result in them deciding not to do so. This pitfall also applies on Linkedin, which is known for having the most discerning and choosy members.
For these reasons I think it's best to post to only one community or group on these two sites in particular. If you do want to repost it at others then give it some time, and make sure that the introduction you're using is unique on each.