Google's come a long way from its famously sparse search page. Oh sure, the spartan look is still the default on Google's default search page, but the company's iGoogle personalized home page keeps getting more visual.

Today, for example, Google announced further graphical extensions with the release of the iGoogle Themes API (define). With the API, developers can now create their own theme or background art for an iGoogle page.

When it was launched last March, Google limited themes to a few it offered at the site. Now, borrowing a page from its Google Gadgets directory, Google is offering a Themes directory for users to post their work and share with others.

As part of today's launch Google posted four very different custom themes from four designers.

"Creating a theme is very simple; an XML file points to the image and there's support for dynamic themes that relate to the current time and geographic location," Jessica Ewing, senior product manager at Google, told InternetNews.com. "This is all about helping iGoogle users better connect with their page. There's a certain amount we can do, but by no means can we cover the unique artistic desires of all users."

Ewing said iGoogle now has tens of millions of users worldwide. Certain elements of a Theme can't be changed, such as inclusion of the iGoogle logo. Ewing said Google takes fair use issues into account, but otherwise doesn't "editorialize" when approving Themes for the directory.

Also, as with Gadgets, the Themes directory will soon include profile pages for developers available for users to see.