Some people starts to worry that Instagram would be completely ruined by Facebook because of the acquisition. That may not be. But if you really hated Instagram now, you can easily export all your previous photos with the following method.
Visit Instaport at here at first. Follow the on-screen instructions by signing in with the Instagram account. The photos are packed in Zip format.
The site is saying they are experiencing high traffic now. Looks like many people are really scared about the news. If you are experiencing any problems, you should try again in the following days.