Google has unveiled a new look for its free e-mail service that has more white space, less clutter, threaded conversations, new themes, and better search.

Over the next several days, users will be prompted to switch to the new Gmail design with a link in the lower-right corner of their inbox. Eventually, it’s going to become the default.

“We’re excited to finally share Gmail’s new look with you,” Google user experience designer Jason Cornwell said in a blog post. “We’ll be bringing these changes to everyone soon,” he said.

“But if you’d like to make the switch right away, we’re rolling out a ‘Switch to the new look’ link in the bottom-right of Gmail over the next few days.”

The new layout has a revamped “conversation view” to help users read through e-mail threads. It has improved tools for searching mailboxes, which typically serve as storage bins for users.

Google also began providing more insight and control regarding how ad pitches are personalised to users.

Information such as location and search history is used to decide what ads people might find more useful, according to Google.

People can use Ads Preference Manager tools to tune systems to their tastes or block messages from advertisers that are of no interest to them.

A new, streamlined conversation view that displays Google profile pictures for your contacts — making an e-mail thread look a little more like an instant messaging conversation.

Elastic density, which means that the spacing between items on the screen will automatically adjust based on the screen size and device you’re viewing it on.

Instant messages (Google calls them conversations) now come with photos and the messages have a better streamline like a real conversation.

Adding a social element, Google is adding profile pictures beside each message.

The density of the text also adjusts depending on your screen size and resolution, making it easier on the eyes.

The new design is in line with some of the changes Google just made to Google Reader in terms of spacing and overall feel.

Gmail is also prettying itself up with a host of new themes with background images from iStockPhoto.

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