Though the least of my concerns about Black Widow in Captain America: The Winter Soldier is who she's interested in romantically, Tor.com turned up a subtle touch referencing Hawkeye. The Avengers film hinted at a past for Black Widow and Hawkeye and also alluded to a future relationship. I'm a fan because I like to imagine that superheroes occasionally get to enjoy happy personal lives.They deserve it. To that end, check out a close up of Black Widow's necklace in this photo:
I don't want to read too much into it, but unless she's a fan of Merida and Katniss, I like to think this arrow is because of Hawkeye. And that makes me smile.