Today marketing automation systems enabling advanced segmentation allow companies to send highly targeted email communication. Practices such as dynamic content have been introduced to create a near 1-2-1 experience between the user and the brand; and with more emphasis on relevance and engagement in order to achieve a good email reputation, quality is replacing quantity as a strategic approach to email marketing.
Source: http://www.smartinsights.com/email-marketing/email-communications-strategy/email-marketing-evolution/