I have been an active member at Stack Overflow for more than an year. And I have noticed that as Stack Overflow started introducing so many sub sites of Stack Overflow, no of visitors got splitted among multiple sub sites resulting in late answers to the questions and ultimately fall in visitors.
For few 3-4 months, I saw a decline in myself in usage of Stack Overflow. Reason is not because I have less questions and I usually know more solutions but reason is that I can find an answer to my questions in lesser time than posting it on Stack Overflow.
Now a days if I posts a question on Stack Overflow, I usually gets an answer in 6-7 hours atleast which was previously 3-5 minutes and that counts a lot.
Is it an end of Stack Overflow for me. Because I cannot wait for a question to be answered at such a long time and rather opt for searching.