I don't know about vodka.us.tt. It is a third level domain. They have many sub-domains for this, but us.tt is not listed and search shows that vodka.us.tt has not been registered: co.tt, com.tt, org.tt, net.tt, biz.tt, info.tt, pro.tt, int.tt, coop.tt, jobs.tt, mobi.tt, travel.tt, museum.tt, aero.tt, or name.tt. co.tt, com.tt, org.tt, net.tt, biz.tt, info.tt, pro.tt, int.tt, coop.tt, jobs.tt, mobi.tt, travel.tt, museum.tt, aero.tt, or name.tt.
It looks like most (or all) of the top keywords are available as second level registrations for $1000. Why would someone pay top dollar for vodka.us.tt when they could have vodka.tt? And why would you register vodka.us.tt (i don't think this is even valid) when you could have vodka.co.tt or vodka.com.tt for the same price of $100.
Tom