Version 7.x-3.x is currently the recommended and supported release for Drupal 7. It is a complete rewrite to take advantage of new features available in Drupal 7.
The 7.x-1.x version is no longer supported.
This module provides web content providers with the means to earn revenue from visitors by displaying ads from Google AdSense™ advertising service on their sites.
Why should you use it:
The module provides easy-to-use ad blocks.
You can easily disable the ads for certain roles.
Provides simple controls for troubleshooting the ads before going live with the site.
If Google changes some minor details in the script, your code can be updated site-wide just by upgrading the module.
AdSense for Search and Drupal 7 are incompatible as both use the 'q' query for different purposes. Using this module, you can display the search results in your site.
If you want to do ad revenue sharing, there's really no other option (D7 version only atm)
Why shouldn't you use it:
Strictly speaking, this module is not in compliance with the AdSense TOS, since you're not exactly copy-pasting the script code in your site. No one has ever reported being banned because of using this module, and Google knows of its existence, and seem not to mind.