It is always important for the IT people to know that:
1. Which language is rising exponentially?
2. Which language is in high demand?
3. By having knowledge of which language we can grab more job opportunity?
4. Which one is the highest paying language in your country?
And many more Just like ever year Tiobe has done complete survey and displayed the result for top 10 programming languages of 2010 and have compared from previous year. Just have a look over it.