If you've arrived here and want to get into one of the groups (Aspects and others), here's how to join. Some groups are open, some are closed (which can't be applied to), and some can be applied to.
1. Click your name on the upper right of any page and click User Control Panel from the dropdown.
2. From the tabs there, click Usergroups.
3. This is a full list of groups available here, with their Open/Closed/Etc status. Select the one you want to join by clicking the radio button on the right under the Select column.
4. Make sure "Join selected" is selected in the pulldown menu bottom right under the Select column and click Submit.
Bonus: This screen is where you also change your default group.
Hope that helps.