In CRM 2011, we have found the new feature for the lookup type fields that you have the ability to see the most recently used items for that lookup while creating the records for entity.
Also you can disable this feature as well by default it is enable for all lookup types fields. If you like to see those items then, during creation of record, you need to “Double Click” on the lookup field.
See the below example for details:
• Below we have shown the account form which has the lookup field “Parent Location” and “Disable most recently used items” option is unchecked for this field as shown in below screen shot.