OP is a web-tech blogger and he just now learned this? I don't use G+ much so I can't easily evaluate the rest of OPs assertions, but I am questioning them by default because when someone makes one statement I know to be false (or in this case inexcusably ignorant), it calls the rest of their statements into question. This is unfortunate because I think much what OP says is useful, but, c'mon: if you blog about web tech and didn't know google tailors results, it makes you seem like you "don't know how any of this stuff works" and I can't take you seriously in that regard.
I am very confused by the section about plagiarism/mis-attribution/non-attribution. OP says his work was "almost-unattributed" but I couldn't find any link back to him on the G+ posting. Did someone click the share button, or paste in a link to his article? Or did someone copy and paste his article? If it's the latter, this phenomenon is much older than the Internet and has nothing to do with G+, specifically, besides the fact that Google may rate your plagiarized "work" higher than the original on its results (which is a distinct issue that applies to both plagiarized and properly-attributed posts).
EDIT: I see the name now, it was next to the title in the post. Thank you OP.