Well if you are a 'teen' then the answer is yes!
A recent survey found that 3 out of 4 teens favored IM over email. With adults this number was reduced to 1 in 4. The survey also highlighted a number of trends such as adults tend to prefer audio chats more than teens.
The most interesting fact of all is that more girls said they couldnt imagine life without IM (36%) than boy (25%). Imagine now much money it saves on parents telephony bills :-)