• The following special picklist fields are not available for record types because they are used exclusively for sales processes, lead processes, support processes, and solution processes:
  • Opportunity Stage
  • Case Status
  • Solution Status
  • Lead Status
  You can use these fields to provide different picklist values for different record types by assigning a different process to each record type.
• Person accounts are account records to which a special kind of record type has been assigned. These record types are called person account record types. Person account record types allow contact fields to be available on the account and allow the account to be used in many situations as if it were a contact. A default person account record type named “Person Account” is automatically created when person accounts are enabled for your organization. You can change the name of this record type, and you can create additional person account record types.
• You cannot delete all the record types for an object if the object is referenced in an Apex script.
• You cannot deactivate a record type if it is in use by an email routing address for Email-to-Case or On-Demand Email-to-Case.
• To create record types for campaign members, click Your Name | Setup | Customize | Campaigns | Campaign Members | Record Types.

  Record types can only be assigned to campaign members using the Campaign Member Type field on new or existing campaigns. To assign record types to campaign members, add the Campaign Member Type field to the campaign page layout. You must have the Marketing User user permission to change the campaign member type. You can also add a read-only Campaign Member Type field to the campaign members page layout.

• The following campaign member picklists are not available for record types:
  • Status
  • Salutation
  • Lead Source
• Salesforce recommends creating no more than 200 record types. While there is no limit, organizations may have difficulty managing their record types if they exceed 200.

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Consider you have a picklist with values A,B,C,D,E. Now, for user X(with profile XProfile) you want to show only 3 values A,B,C and for user Y (with YProfile) you want to show 4 values B,C,D,E. So you create 2 record type - RT1,RT2. In RT1 the available picklist values are A,B,C and make it default for XProfile, similarly for RT2 make available B,C,D,E and make it default for YProfile. Now when the X and Y users log in they can only see their respective picklist values.