Well I don't think is that bad here in Mexico, I went to a Telcel Store yesterday and found a special that had a Galaxy S3 for free on a 24 month contract for $599 MXP (close to $45 USD tax included). The plan had 130 minutes nationwide and 3GB of data, no so bad as I personally don't use SMS.
But everyone here in MX seems to hate Telcel somehow...
Here in Colombia , I get unlimited everything for $25 a month. 4g is an extra $15 us a month, but again unlimited. I don't know which providers they got their data from for South America, it seems a bit high.
The big operators are Telcel (América Móvil) owned by Carlos Slim, movistar (Telefónica, from Spain) and Iusacell, the little guy compared to the other two but with the monster that is Televisa right behind.
at&t and Verizon went out from Mexico a long time ago.