I don't think it is a waste of time.
It is a faster way of speaking to someone, easier, and costs less. Think, you speak to someone in England, (say you lived in Australia), on the phone, and it costs quite a bit of money for the bill payer. But with instant messaging, you're not really paying anything.
Instant messaging and the internet is also a great way of meeting people you wouldn't normally meet. Friendships are formed, relationships are formed, (I know couples who have gotten married, but wouldn't know eachother, if it wasn't for the internet), and it is a, as I said, faster and nicer way to speak to people. Also, not everyone finds it easy to speak on the phone, or meet people sometimes.
I myself have made quite a lot of good friends on the internet, who I do plan to meet someday. You may say, "but oh, he/she could be a pedofile!", but you can get to know someone very well over the internet, and you normally see photos of them, see them on webcam's, and even, after a time, phone them, to see what they hear like.
Plus, I have had friends on the internet who have helped me a lot more than anyone I actually see on a regular basis ever has. (Bar my mum and bro.)
I also like MSN because it gives me a chance to say what I feel, and to speak my mind. I am confident on MSN, more confident than I am face-to-face. I think this is the same for a lot of people. You can build friendships over the internet, which you wouldn't be able to achieve face-to-face. Not saying that you'll only ever speak to them on MSN, because most likely, you'll meet them properly one day.
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