It'd be nice if fieldset and legend tags were output on the registration form. The elements included in each fieldset (and their tag) would reflect the tab management setup in the back end.

The FIELDSET tag groups form elements. The LEGEND tag ads a title to the FIELDSET group. The FIELDSET and LEGEND tags clarify their purpose of your form. This would help the understanding and clarity of CB registration forms.

People using visual and non-visual browsers benefit when you use the FIELDSET and LEGEND tags on all your forms. The FIELDSET tag itself can be styled with CSS the same way any block level element can be styled.

For visual styling, it'd be nice if each fieldset had two CSS classes applied to it. One CSS would be generic, like "cb_fieldset" and the other would be specific to the group (such as "cb_usernamepassword".