Google today officially added (previously in Preview section) a new feature, Google Mapplets, to Google Maps that enables users to add third-party contents to their Google Maps “with a single click and to save these customized maps to their personal library of maps.”

Some of the featured contents you can add immediately after getting on Google Mapplets are Geotrends, Google Real Estate Search, Photos from Panoramio, Gas Price from GasBuddy.com, Distance Measure Tool, Our Earth as Art, and Crop Circles, but the Google Maps Directory also hosts over 100 Mapplets.

At its initial launch, Google Mapplets is already available in English, French, Italian, German, Spanish, Dutch, Danish, Finnish, Norwegian, Swedish, Russian and Traditional Chinese.

Building your own map application using the Google Mapplets platform is easy, if you are interested, check out the documentation and get started! :)

I am not sure if you can add iGoogle gadgets to your Google Maps, but well, Google says you can. LOL. :)

[thanks Kate Hurowitz, more on Google LatLong Blog]