NEW YORK ( TheStreet) -- TheStreet contributor Eric Jackson thinks there's a war brewing between Twitter (Proposed Ticker Symbol: TWIT) and Facebook ( FB).Jackson uses photo sharing to illustrate the fight. By happenstance, I deployed Facebook-owned Instagram to Tweet a photo shortly after reading Jackson's article. As part of the Tweet I used the @ icon to mention TheStreet. I hit share and checked my Twitter feed. My picture, along with everything I typed into the iPhone Instagram app was there, except the '@' in front of TheStreet. It disappeared. I tested it several times. Same thing happened repeatedly. Instagram turned @TheStreet into 'thestreet.' It hyperlinked URLs I included, but rendered Twitter mentions unclickable. I'm not sure if Instagram has been doing this all along. If not, and it's a Facebook move, it's not earth shattering, but it does speak to the competitive nature that exists between Facebook and Twitter. As Jackson predicts, the photo-sharing wars will come down to a battle between Apple ( AAPL), if it makes a meaningful move into the space; Yahoo ( YHOO) via a rejuvenated Flickr; Facebook; and, once it rolls out its photo sharing platform, Twitter. Multiple companies can coexist in the space if they find creative ways to carve out niches. While it's a great story and worthy fight, when you drill it down to Facebook and Twitter, few places exist where the two companies should even bother competing. In fact, it's almost pointless for them to beat one another over the head. If there was ever a case of clean coexistence in the Internet/tech/new media space, this is it. Facebook and Twitter should work to maintain their distinctions. You use Facebook to connect and reconnect with family and friends. You put pictures of your kids on Facebook. It just feels like the more appropriate environment for that sort of thing. Twitter isn't about friends and family. Or keeping grandparents updated on Junior's latest growth spurt or developmental milestone. You follow people who can do something for you intellectually at Twitter.