Get your geo plugin here

It's not all that fancy, but it sure is easy to do:
33 lines total which includes about 6 lines of PHP which consists mostly of building the URL to the map tile service. Then the Javascript which has a callback function to read the form values and make the backend GET request and a simple function to take the JSON response and add the map tile to the document. And finally the actual HTML form.
With a slight tweak you can change it to make a nice geocode lookup field.
So, fire up your text editors and start writing some plugins for blog and forum packages and perhaps image gallery applications as well.