When you log onto Facebook, it's almost as if Mark Zuckerberg has been reading your mind when you see the advertisements to the right of your screen. This, along with its integration into practically the entire Web, is what keeps this network going. Instagram never had an "all about the Benjamins" feel, but users will more than likely see a greater effort to make money from the photo sharing app very soon. Hence, pop-up and banner advertisements.
Facebook filtering is a possibility
Zuckerberg also stated on his page that: "We will try to learn from Instagram's experience to build similar features into our other products." What is particular about the Instagram sharing experience, is the filtering of users' photos. This means, that Facebook may offer some version of its own photo filtering. If this is brought to Facebook, there will not be much left to Instagram.
As it stands, Instagram is primarily a mobile app, with very limited access available from a desktop. If Facebook chooses to keep ads off of the mobile version, they will probably build a fully-functioning Instagram website where they can advertise. This may not be such a bad idea, but the site will be subject to being changed as often as Facebook's site is altered (almost every day). Will an Instagram page resemble a Facebook timeline? We hope not.
Everyone will be on Instagram.
Remember when Facebook was exclusively for college students? Well, that went down the drain when it started to make more money. The same thing is starting to go for Instagram; its popularity has taken the app from iPhone-only to Android-friendly. With Facebook now at the monetary forefront, you can be sure that your mother and 14-year-old sister (who made their way to your Facebook), will soon be following you on Instagram.
Expansion of the Instagram interface
Besides filtering, Instagram users have fallen in love with the app's simplicity. Currently, the Instagram experience is just posting, liking and following. For Facebook, on the other hand, the experience continues to grow more and more complex. Facebook is looking to revolutionize social networking, and has sought to include newer ways to do this, none of which include simplicity. Instagrammers will probably see more features come to the app, like statuses and more ways to pry into your followers' lives, which is another thing Facebook has been good at.