They are customers of the CDN too.
Briefly yesterday, linkedin.com was down with Cloudflare's internal server error page.
I don't think that's necessarily a bad review for Azure services, there are other explanations, like organizational inertia, contractual agreements, team preference.
You can feel the pain of GitHub migrating to Azure from afar. With a beast that LinkedIn is, there's got to be a good prize for someone at the end of the road before they pull the trigger.
