• Apps that have pushed updates recently are crashing, so developers should not be pushing updates to their apps.
• Users are blaming the developers, when in fact something is wrong with the app store.
• Marco Arment, creator of the Instapaper app, posted his experience with the issues to his blog, which helped raise awareness of the issue.
• Apple has released a comment: “We are aware of the issue related to apps crashing after update. We are currently working on resolving the issue. Stay tuned for updates.”

From the article:

We leave the Internet for 24 hours, and this happens: Something is seriously wrong with Apple’s app store. As in, if you updated Instapaper or Angry Birds Space HD Free yesterday, there’s a good chance it just crashed upon launch. Users are having to perform clean installs, while developers are dealing with annoyed users who assume the fault lies with the app itself.