This option is still available, but from what I can see you can't customize your profile?User Customizations:
Show User Customizations
Hide User Customizations
Other users can make customizations to some of their pages, such as their profile page. With this option you can choose to hide these customizations.
The only customization you can do is to edit the background image/colour (but only you see this, not everyone)
why was it disabled? :p
or am i missing something