From International Research Institute for Climate and Society (IRI) :
IRI ENSO Update
Latest Summary of ENSO Model Forecasts (ENSO forecast plume)

 
From NOAA Pacific Marine Environmental Lab (PMEL) :
Latest mean SST and Wind Anomalies in the Eq Pacific: 5-day and Monthly
Latest Equatorial SST Depths: 5-day and Monthly
Latest Zonal Wind, SST and 20ºC Isotherm Depth Anomalies: 5-day and Monthly
Latest 5-day 20ºC Isotherm Depth and Winds

 
From CPC/NCEP:
Latest 12-week SST Anomaly animation
Latest ENSO Diagnostic Discussion (updated monthly)
Latest Weekly ENSO Update (updated every Monday): PDF or Powerpoint
Prognostic Discussion and Seasonal Outlook for U.S. Mainland and Hawaii
Precipitation Forecasts for the Tropical Pacific Islands from CPC
Latest Micronesia/Guam ENSO-related Accumulated Precipitation: 30-day, 90-day and 365-day
Composite Rainfall of ENSO for Pacific Island Stations

 
From NOAA Earth System Research Lab (ESRL):
Latest mean SST Anomalies: 7-day, 30-day and 90-day
Latest mean OLR Anomalies: 7-day, 30-day and 90-day
Latest 12-month SST Anomaly animation

 
From Bureau of Meteorology (BoM), Australia:
Latest "Weekly Tropical Climate Note"