At the moment the Preliminary Examination consists of two papers of objective type (multiple-choice questions) carrying a maximum of 450 marks.
One is a general studies paper and the other the subject of your choice like history and geography. The UPSC is now scheduled to adopt a New Pattern and as per this UPSC Pattern there will be no subjects to choose from thus making the New UPSC Syllabus the same for everyone. In the proposed UPSC Pattern 2011, they plan to have a gs paper and an general apptitude paper. This UPSC Pattern Change enables a single marking system and does not need moderation as was prevelant earlier. As per the older syllabus people forcefully chose subjects that they believed were scoring but then had to face more competition within it. As a preliminary test the new syllabus seems more fair.
This new pattern will be called the Civil Services Aptitude Test or CSAT. The CSAT is expected to come into effect from Civil Services Examination, 2011. CSAT will not only enable us to choose civil servants with right aptitudes but also end the use of scaling system for varying subjects that has been a matter of concern for many.