That's called being an arrogant homer, aka niners fan. Lol. But really, I think it's important to not say "oh we're gonna win the superbowl this year" every single year. Yeah you can say it jokingly to exude confidence, but any more than that makes a bad impression in my opinion. Of course, if you truly believe that then that is fine. I don't think anyone else would see that this year though haha. No one like obnoxious fans.
On topic, like I said, I think 10-11 is a decent possibility taking into account factors from last year, but 12 might be pushing it. I'd be glad to be proven wrong though.