I run SmugMug, a popular photo & video sharing service with over 35M visitors a month, and I just implemented Twitter Cards last night.
While we have billions of photos & videos served from *.smugmug.com, we also have many tens of thousands of custom domain names our customers use, so you’d never know they were coming from SmugMug at a surface glance.
Does the Twitterbot and/or Twitter Cards mechanism have a method to handle URLs like these? There are a couple of approaches, but other large social media services that have integrated SmugMug support tend to use DNS since all of those custom domains are CNAME’d to ‘domains.smugmug.com’:
Is this possible? Is there some other solution we can collaborate on?