OV are considered more secure than DV due to the higher registration requirements[0]. Additionally a DV certificate is good for a single domain, OV certificates are good for all of that organisation's domains. For example the NYT's certificate is valid for:
DNS Name=nytimes.com
DNS Name=*.blogs.nytimes.com
DNS Name=*.blogs.stg.nytimes.com
DNS Name=*.dev.nytimes.com
DNS Name=*.nyt.com
DNS Name=*.nytimes.com
DNS Name=*.stg.nytimes.com
This simplifies deployment significantly.