UPDATE March 2013: this article is now out of date as the Google+ Profile Page has been updated again.
1) Photo Changes
Google have introduced a Cover Photo to Google+ Profiles. (It's got a minimum size of 940x180) You also have the option of keeping the old style five scrapbook images.
The Profile picture is also bigger (250x250) which means you need to up the quality of those blurry profile pics you reused from Twitter last year.
2) New Hovercard
Previously the "Hovercard" (the pop up image when you mouse over someone's name on G+) was made up of just your Profile Picture and one line of text that was determined by an often confusing process.
Now it's simple. You have your profile picture, cover photo and up to three editable boxes (Work, Study, Place)
Ticking the "Current" box for Work and Study and making them Public ensures they show up. Also recommend that you place some "About" info after the Employer name.
The "Places Lived" box is slightly different and you need to show your current location by clicking the place icon to turn it blue. (default is green)
3) Links Position
Lastly, Google has moved all your Profile Links to the bottom of the "About" section. (they were previously at the right hand side of your profile.) This makes them about 100x less discoverable and you need to ensure that you add links to other more visible locations.
The best place (right now) is probably the "Introduction" section of the About Tab as it's higher up. (at the top).
OK! There you go. Have fun and put this info to good use.
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