Hmm...practical poiunt of view they are right..But, as for me, for example I have 2 perfect friends from Germany. One of them is a boy, we was on vacations togather in summer 2006, and since that time was never meeting, just sms or icq, or e-mails, but we still interesting in each other and I always glad when we send me messages. The second one is a man, he is 40 years old, from Germany too, we was meeting on social network and never meet in real, but its so interesting to chatting with him!And, by the way, he promice to visit Moscow this summer..So, who says that online friendship could not be real?
P.s. oh, and one more example. On livejournal( internet diarys) I meet girl, she was leaving comments to my posts, we was chatting and than decide to meet in real( she is from Moscow too), now we are the best friends=))
So, friendship is good, no matter if its in network or in real)