iGoogle will allow people to create and share their own themes for iGoogle in the gadget directory…
I made one and it is live now in the theme directory.
This move also injects the concept of “tabs” right into the Google gadget directory….
There are several pages of themes to choose from, I do not think this feature is live for everyone yet, so some may see less than others when going to the iGoogle theme directory.
It is Google’s latest move to increase the level of people personalizing their iGoogle page. The theme directory is also accessible via the iGoogle page link “select themes”. I will speak more of this soon in an article about tabs and themes (and what you can do with them).
To learn more about creating your own theme, go use this link: Create custom themes
Also of SEO interest, check out the “long tail” theme 
tip: if you can’t see all five pages of new themes, here is how. Go to the theme directory, then on the left hand menu choose “most users”
iGoogle Themes API Documentation Help
Uses of iGoogle Tabs
How to Create, Distribute, and Promote iGoogle Tabs
