To me being passionate is the essence of being. I have no problem if others don't always share the passion. I used to be quite vivacious in describing or talking about my passion and although people may not share it they've always admired the enthusiasm. I am careful not to sound too forceful and put people down if they don't share my passion. Also it is a fine line from being enthusiastic about something and boring others silly!
I have also started to listen to other people's passions first, with genuine enthusiasm. For even if the subject of our passions differ, the emotion and the intensity we share may be the same. Then I share my passion and try to see parallels. This way we feel we share a common space, a common emotion only about different things. This is not such a bad thing.
But I agree about the buzz it creates when we meet someone who shares our passions and how instantaneous the understanding and communication could be between those with shared passions. Perhaps that's why we are here in hub pages!