They have always done the Alo shows from reasonable size cities as I recall. 

The largest city that I know of in the Bolivar state is Puerto Ordaz at 1.3 million, but Cuidad Bolivar (good INFO: http://en.wikipedia.org/wiki/Ciudad_Bol%C3%ADvar  GOOD PICS: http://www.venezuelatuya.com/guayana/ciudadbolivareng.htm) at around 350,000 residents is the state capital and far more attractive and historic.

If Hugo were really only interested in aluminum and steel he would probably be going to the hub of those industries in Puerto Ordaz, but AFAIK he is going to Cuidad Bolivar.

Sifontes by comparison is only about 40,000, and the El Callao-Las Claritas region is close to 200,000 but is basically a third world slum. So neither would make sense as a broadcast hub for this Alo.