Twitter accounts updated within the last hour:
viav7 (retweeting distress messages amongst other)
jacinperez (Tweets in Spanish)
LisaTw (Tweeting about Chile)
kamla (Tweets about it)
ontobelli (Tweets in Spanish)
globovision (Tweets in Spanish)
ageofbrillig (Tweets about the possible tsunami)
crisiscamp (Tweets about it)
earcos (Tweets in Spanish)
marc_cooper (Tweets about it)
geographile (retweet geography-related news)
Dhaisy (Tweets about it)
CarlosFoxTV (A “news guy” tweeting about it)
marc_cooper (Tweets about)
W7VOA (Tweets about it)
BreakingNews (Breaking news about it)
AlBoeNEWS (Tweets about it)
1Vzlano (Writes from Venezuela)

Twitter accounts updated within the last three hours:
CNN (Tweets some news about Chile)
marcoie (Are in Chile)
Ciencia_y_Tecno (Tweets in Spanish)
progone (Focuses on the tsunami)

Twitter accounts updated later
RodrigoBNO (Journalist in Mexico)
CNNChile (CNN Chile)
CarolinaMillan (Are in Chile, tweets in Spanish)
quincy12 (Are in Chile, tweets in Spanish)
KiLotr (Are in Chile, tweets in Spanish)
kurenaiteam (Are in Chile, tweets in Spanish)
azadehCNN (CNN reporter tweeting about Chile)
elliottyamin (Are be in Chile, also interviewed on CNN now)
baywatchboy (Tweets about it)
Sipote87 (Tweets about it)

Other resources:
Live TV from Chile (In Spanish)
Tsunami warnings
Images and info from Chile