Do the Instagram photos showing up in your Twitter feed look funky to you today? Twitter says that it's because Instagram disabled its Twitter cards integration — cards are the extension that lets embedded media like photos and videos show up in tweets.

According to Twitter's status blog update:

Users are experiencing issues with viewing Instagram photos on Twitter. Issues include cropped images. This is due to Instagram disabling its Twitter cards integration, and as a result, photos are being displayed using a pre-cards experience. So, when users click on Tweets with an Instagram link, photos appear cropped.

Speaking at the Le Web conference in France, Instagram CEO Kevin Systrom confirmed the change and indicated more are on the way. The change is due, he says, because Instagram now has its own web presence where it wants to direct users. And while he noted that it was confusing for people, it was "the correct thing for our business to do at this time."

When asked for comment, Systrom released this statement:

"We are currently working on building the best experience for Instagram users. A handful of months ago, we supported Twitter cards because we had a minimal web presence. We've since launched several improvements to our website that allow users to directly engage with Instagram content through likes, comments, hashtags and now we believe the best experience is for us to link back to where the content lives. We will continue to evaluate how to improve the experience with Twitter and Instagram photos. As has been the case, Instagram users will continue to be able to share to Twitter as they originally did before the Twitter Cards implementation."

This is the latest dust-up in a fight between Twitter and Instagram that does more to hurt both companies' users than it benefits either business. It's all the more fascinating given how closely the two companies are related. Instagram chief Systrom was an intern at Ev Williams' podcasting startup Odeo, which Twitter grew out of. Twitter chairman and founder Jack Dorsey was an early investor in Instagram, and the photo-sharing service grew largely on the back of Twitter, thanks to its ability to export photos directly to other social networks.

But things have been frosty between the two companies recently. In April, Twitter's rival Facebook purchased Instagram. Then, in July, Instagram was an early casualty of Twitter's new API policy, after Twitter cut off Instagram's ability to access its API to look up friends. This was seen as a move to help keep Instagram, and by extension Facebook, from plundering Twitter's social graph. And in recent months, Twitter has been rumored to be working on its own photo filter and sharing feature, something that would compete directly with Instagram.

None of which should matter to the people who just want to use both companies' products in conjunction, but instead are being treated like chess pieces in a proxy war between Facebook and Twitter. As each company continues to further wall off products, that's just going to get worse, as each takes steps to make its product less interoperable with the other.

It's inevitable that these social-media companies are going to continue to bump up against the other's business models as they grow, evolve and become ever more diversified. One of the more effective defensive actions each can take to preserve their users and business is to make it hard for you to leave their service.

Twitter never wants you to leave its stream. When you see a photo you like, Instagram wants you to click on the heart in its stream rather than the star in Twitter's. And the best way to make sure you do that? It's to yank Twitter's ability to display Instagram media. In short, Twitter started this fight, and in retaliation Instagram brought out the big guns.

While each can argue that the company is just doing what is best for the business, all of those moves to reduce interoperability and cleave the services further apart just makes for more steps and more hassle for the people who have truly built both services into successful enterprises — which is to say the end users. And no matter who comes out ahead, in each of these battles, the people who use and love both networks are the clear and real losers.