Honestly? If you haven't been inclined to watch it so far, I say don't put it on a list of "must watch". It's enjoyable, but hardly very deep. Eye candy, a fun couple of hours, and the fandom is active (which is rather nice from a writing-to-get-readers perspective, although, as per usual, the fandom is not active in any area that I particularly feel driven to read).

Also, I love the characters in their own right, but the movie is very very geared to the white male audience, and it took two viewings before I fell in love with Maria Hill. And Maria is pretty much my sole 'in' to the fandom.

If you happen to have the time and nothing better to do, then yes, I'd say watch it just to get it out of the way. But it's about as cheerfully shallow as a rainpuddle that one can have great fun splashing in, with no deeper meaning beyond what you want to put into it.