The TIOBE Programming Community index gives an indication of the popularity of programming languages. See this site for ranking calculations and results on the top 50 languages:
http://www.tiobe.com/

Here are a few interesting rankings:

1.) C
2.) Java
3.) Perl
4.) C++
5.) PHP

9.) C#

12.) COBOL

22.) VB.NET

25.) Visual FoxPro