Yesterday, LAN Airlines (Chile) and TAM Airlines (Brazil) signed a non-binding MoU to signal their intentions to form a single company, Latam Airlines Group, which would keep both brands separate.
A sampling of news items:
Planned merger completion by mid-2011 (FlightGlobal)
Final association to global alliance not yet resolved (FlightGlobal)
HL, 2335h CLT, 14 Aug 2010.