The best rated Picasa plugin for WordPress, PWA+PHP, puts your public and private Picasa albums on your site in your language!
v0.9.6 Update: Bug fixes. See changelog.
PWA+PHP is a lightweight solution for displaying your private (unlisted) and public Picasa Albums within WordPress in your language using Fancybox, Shadowbox or Lightbox. The plugin provides a guided installer that helps you generate your gdata token and set display options for your albums.
PWA+PHP extends the capabilites of Picasa albums, allowing you to group albums by keywords in the title. Using this capability, you can create several photo pages in WordPress and show different groups of albums on each page. You can even allow users to download full-size copies of your images.
PWA+PHP's configuration options allow you to customize the look and feel of your albums, including thumbnail and image size, images per page, caption settings and display language, without modifying any code. The included CSS file can also be tweaked to your liking for an exact match with your existing website. The div-based layout is fluid and adjusts automatically to fit your theme.
Check out the demo to see the code in action.