Gmail Makes it Easier to See Pics From Family/Friends
In the past Gmail has hidden images in email messages by default. If a user wanted to see images contained within a message, they had to click "display images below" to get them to show up.
This policy is still in place for messages from unknown recipients, but now images will automatically be displayed if they come from a contact. More specifically, if you have emailed a person at least twice, you will see images from them without having to click the "display images below" link.
The process has always been a way of protecting user privacy from spammers, but a lot of the time images come from friends and family, and having to click the link has simply been an added hassle. If you know the person sending you images, privacy isn’t really an issue.
"And we only display images by default for authenticated messages (using SPF or DKIM)," explains Google Software Engineer David de Kloet. "Gmail and other big mail providers usually authenticate their mail, but other services might not, so it’s possible you’ll get an email from one of your contacts where images aren’t displayed by default."
Google does note that while 2 messages are currently required for images to display, they may change this in the future if the number doesn’t "seem right."
It is possible that you like Gmail’s non-image-displaying just fine. You can keep it this way if you go to "external content" on the general settings tab and select "ask before displaying external content." You can also disable images on an individual sender basis by clicking "don’t display from now on" under the "show details" link in an email that contains images.