So what happens to all of the regional operators that own leases to continentals name? Do they just become United Express?
Correct, they will all serve the combined company, which is saying its name will be United. This merger will be slightly different than the Delta/NW merger, which was basically a takeover by Delta. All of Delta's regionals still exist, but call themselves Regional Elite as a group, even though the planes say Delta Connection, and each individual carrier retained their callsigns.