Come on admit it, you gotta love how Google refuses to let a free app rest on its laurels.  Not only did they add text messaging and then video/audio chat to GMail, but now they given you the ability to make it look the way you want with custom themes. 

Just go to settings in your Gmail account and select on of the 30 themes that are now offered.  If you don't like any of them, just wait a few days, I'm sure the community will chime in with dozen's upon dozen's very very soon.

Google

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