I got a Letter from the Univeristy of Chicago?

I'm a sopre in High School. This upcoming fall I will be applying to Colleges. So far on a daily basis I receive 3 or 4 letters from colleges all over the country telling me why they would be the best choice for me and how I fit their criteria. Most of them have been average schools and nothin so far has caught me mind. Well today I received a letter from the University of Chicago. In the letter they explained that considering my academic success and my recent PSAT scores they would like me to look intot their school and so on. Now I haven't taken my actual SAT's yet but does this indicate that they have possible interest in me? I mean this is the University of Chicago. This is almost like saying Brown or Duke or Dartmouth. i mnea does the University of Chicago send letters to any high school student or do they have a set lis of students around the country that fit their criteria of Chicago college worthy sudents? I never contacted them or asked them to send me anything.