Who actually owns the domain you build your site on? If ClaimYourName.io gets people to register their own name as a domain but retains ownership that could turn ugly if you wanted to leave the service and keep 'your' domain name, or if ClaimYourName.io goes under.

In the small town where I grew up the One Guy at the biggest web agency quit in anger, and since nobody else at that company had the passwords to liberate the domains, dozens of businesses in my town had to buy new domains and reprint all their material with new URLS on it. What a headache :S