Google mail, known as Gmail, one of Google's most popular tools, has joined in the cavalcade of updates to the search giant's numerous applications. Google Reader joined the ranks of Google+ this week, and now Gmail users can switch to the tool's new look by finding the switch to the new look button in the bottom-right of Gmail. The switch to the new layout is not permanent yet, hence the preview, and Google hasn't said when the changes will be finalized. Given that email is a popular tool, the changes are likely to cause an uproar. So here's what you can expect, the top five new changes made to Gmail.

Searching through your email catalog has been revamped, and there's now a dropdown menu in the search box that has filters for to, from, has attachment among others. Next, when you scroll down to see all your messages, the whole page no longer goes with you. The navigation panel on the left keeps your contacts in view at all times. Additionally, if you want to see more of your folders than contacts or vice versa, you can resize those areas or hide one or both completely.

In the past, when a series of emails went back and forth between people, the conversation appeared to run together because it was kind of hard to tell who said what in the exchange. Google addressed that by putting each sender's Google profile next to each message, that way you can tell who said what.

Because Gmail is used on different sized screens, Gmail will automatically change the layout depending of if you are on a mobile device or laptop, for example. Of course, you can also now adjust how closely together you want your messages to be spaced. Choose from Comfortable, Cozy or Compact settings. Below is a Google video with a sneak peak of the changes.

Finally, themes have been completely rebuilt and include a new set of high resolution themes with imagery by iStockphoto. Many of the old themes have been updated and your theme will be automatically carried over to the new look.

Let us know in the comments if you're amenable to the new-look Gmail.

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