Working with @BBlack on setting up the launch in March, we identified that running our DNS at enterprise.wikimedia.org could create potential privacy issues around cookie sharing with our external AWS infrastructure. This was due to the .org acting as a parent on a myriad of our projects and creating PII. Our fix to this was to use enterprise.wikimedia.com which is nothing more than a dummy redirect for .org typos. We also felt this was somewhat authentic to the nature of "for-profits" within "nonprofits". See more on our FAQ
One unaddressed point (that we didn't need to fix at launch but need to think through now) is the mixing of SLAs between the two infrastructures. My understanding is that having WME's DNS tie to an internal hosted domain makes a dependency on the up-time of WMF's DNS...which in spirit is not bad but creates dependency when ideologically there shouldn't be.
A temporary solution to this was to host our beta and launch APIs on wikimediaenterprise.org, which allowed us to own a domain without SLA implications that is related to the project. But this is not a long-term solution.
So right now we have enterprise.wikimedia.com as our landing page to sign up, and api.wikimediaenterprise.org as the host of our APIs.
We would like all of the work for this project to exist under enterprise.wikimedia.com: APIs, Landing Page, Dashboard, Docs, etc.. This requires us to move the DNS of wikimedia.com to Wikimedia Enterprise's AWS based infrastructure and keep all the redirects to WMF infrastructure (wikimedia.org). This will allow us to host our beta and launch APIs on enterprise.wikimedia.com without muddying the SLAs together, this is a small yet core element of good user experience of WME customers.