On most entities in CRM v3 and v4, you can safely customize entity views, whether the entities are core CRM, or custom ones that you create.
On the Marketing List, however, you may have notice that you cannot add columns to the marketing list members view. Use the workaround below to enable you to customize the members view using a direct URL link. Replace the http://crm/ portion with your CRM server name.
Member type: Accounts
http://crm/tools/vieweditor/viewManager.aspx?id={51DE84DD-732F-440F-A506-26123A19AB50}
Member type: Contacts
http://crm/tools/vieweditor/viewManager.aspx?id={2F0D0EDE-D356-4B1E-83BD-E978F10E3EEB}
Member type: Leads
http://crm/tools/vieweditor/viewManager.aspx?id={FC1B8995-4E44-4D65-99BE-1E945953564C}
When finished, remember to publish all customizations.
