PACER’s U.S. Party/Case Index has been replaced by a new search tool called PACER Case Locator. It appears that the underlying data is the same – Case Locator just offers improved search and display capabilities including the ability to:
- request lists of cases for a specified date range by court type;
- conduct searches based on chapter, discharge date and dismissal date for bankruptcy cases;
- access case information for the Judicial Panel on Multidistrict Litigation;
- choose result formats, including HTML, delimited text, and XML which can be easily imported to other programs for analysis;
- change the sort order of the results displayed; and
- conduct refined searches within the results of a previous search.
Here’s a screen shot of the new Case Locator interface
As you can see from the old U.S. Party/Case Index screen shot below, it was high time for an interface upgrade. The U.S. Party/Case Index will be available for the next few months to allow users time to become familiar with the capabilities of the new Case Locator. 
I’m not sure why they changed the name though – but I never like it when databases change names.
Source: Legal Dockets Online Blog