The way the pre-registration process for non-trademarked names will work is sort of interesting.
There was no official "Landrush" process defined by the Registry for .us names. The "Sunrise" or trademarked names had a formal process, but there's nothing for Landrush.
A number of Registrars started to collect names with the plan to submit them to the Registry as soon as the Registry begins accepting real-time registrations on the 24th. OpenSRS is one of these. There are actually not many doing so - most seem to be waiting until the Registry opens on the 24th.
What OpenSRS has decided to do this time - as opposed to prior pre-registrations - is to accept duplicate submissions from their Resellers.
Why? Well remember I told you that my OpenSRS account needs to be fully funded for me to "cover" the domain registrations? Well let's say you pre-register a domain with someone who is not going to fund their account at the 100% level. What happens when he runs out of money in the middle of the registration submission process? All the domains he has left in his queue will be lost. So, if you have a pre-registration in at another OpenSRS reseller who is fully funded, then the name the first reseller did NOT get, will be won by you - even though you registered it later than the other person, who unfortunately chose a reseller who is not funding at the 100% level.
OpenSRS has not offered up all the details on how they are processing orders - as this lets the competition in on their secrets and that's probably not a good thing. They do believe they will have a high rate of success however.
This one will be interesting, since at this time, there is no round-robin process at the Registry, it will be first come, first served when the Registry opens up it's processing queue for it's Registrars. Should be fun

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-t