Last week Gmail began to cache images for messages received by its users. This caused an uproar within the email marketing industry, as this action negatively affects a marketer's ability to track total opens. If a tracking image pixel is cached, it can only be used once - all subsequent opens of that image would not tracked. Since this was first noticed, there have been many public discussions among email marketers about why Google would make this change. Well, it looks like we now have our answer.
Google announced today that it would begin showing images in messages by default. Gmail indicates that now "your messages are more safe and secure, your images are checked for known viruses or malware, and you’ll never have to press that pesky 'display images below' link again."
This would appear to be a win for marketers and consumers. Marketers' messages will now display the way they intended them to, and they will likely see an increase in unique "open" data as the tracking pixels should be enabled by default as well.
The one initial downside could be a decrease in total opens due to the issue mentioned above; however, the usefulness of the total opens metric has been under debate for a while. The good news for consumers (and marketers) is that they will no longer have to click to allow images to be displayed for every message they receive.
You can read about it more on the Gmail Blog: http://gmailblog.blogspot.be/2013/12/images-now-showing.html
UPDATE 12-13-13 - It looks like Desktop Gmail users started getting images on by default today with mobile users being affected in the New Year. More information can be found at MarketingLand and Washington Post.