Is it possible for two people to think they've regged the same domain name? Both recieve confirmation and see it in their accounts, and there is no whois data to prove either way?
Any registrar can "say" you have the domain in your account and allow you to "manage" it. However waiting for the whois to update and checking that is the best way to find out who owns the domain.
Well after GoDaddy send you 347 emails trying to upsell you on domain addons, one of you will get an email saying that they are sorry but the name is not available. 27 months later, the refund will be forthcoming. Actualy both of you could get that email as the name was probably never available to either of you.