I'm using a Sony Experia S with Gingerbread (2.3.7) and I'm having the same issue.  I have disabled Instand Upload in the Google+ app (went to ... More -> Settings -> Instant Upload, and checked the box to turn it off.  The box is unchecked, it now says "Turn on Instant Upload" (which should indicate that it is now off).  When I hit back once, it shows "Instant Upload" with the status "OFF" and it is grayed out).  Yet today, when I took some pictures, they got uploaded to my G+ account.  When I logged in on my laptop, there were my pictures, in a private album, ready to be shared.  This is using up unnecessary bandwidth (my camera takes 12MP photos, so you can imagine how much bandwidth it sucks up with just a dozen pics).  My phone creates a separate album in its own storage (so it duplicates every photo that I take, which is definitely not something I want) for Instant Upload photos and I can delete neither the album nor the individual pictures in it on my phone.  I can only delete them when I get into the private album in G+ on my laptop, but that doesn't get rid of the extra album on my phone, which is pretty much untouchable.

Please, please, please, someone repair this bug.

Thank you much.