Quite a grandiose claim on my part. But read on, and you may agree (and whether or not you do, I'd like to hear from you).
It seems to me that Web 2.0 tools have changed children so much in the last 5 years that one could say with some reason that we have been present at the birth of a new form of homo sapiens. I call it "Homo Connectivus".
The kids I know have not twice as many, not 10 times as many, but HUNDREDS of times as many social connections than my generation had, through MySpace and other Web phenomena. A 12 year old child today may have hundreds of online 'friends', has shared thousands of videos, and Lord knows how many podcasts and music downloads.
This means that the nature of personal identity itself has changed. Kids today are so immersed in the worlds of thousands of other people that there is a great deal of blurring between who 'I' am and who 'they' are.
The Web has become a kind of 'connective tissue' that links people together so strongly that they seem like a new life form. (This has happened to a small extent to you and me also, but I think the real change is among people under 13 because so many of their personality structures were not fully formed at a time when they were already communing with hundreds of others online. Thus, you and I think of social networks as a new 'tool', whereas young kids see their social networks more as a big part of who they ARE.)
I don't think it's out of the question to call today's connected children a new species, because it's comparable to what happened on Earth 3.9 billion years ago. The first life forms were single celled organisms that had to perform every life function themselves. But as millions of years passed, cells found that by 'teaming up' with other cells, and developing specialization, each could benefit the larger whole, which led to complex multi-cellular organisms, including (eventually) us.
Kids today experience life in a radically different way than you and I did at their age. If they create art, or music, or video, they already KNOW at age 10 whether hundreds of others think they have talent or not, and they've already been cross-fertilized by so much other art that they are in effect already a collaboration.
If they have a notion that they'd like to be a teacher, or a writer, or a scientist, they already KNOW what hundreds of others think about these claims, and their efforts have already been 'edited' so many thousands of times that it's hard to separate the individual from the group.
Is this good or bad? I think a case can be made for either. But essentially it's just another step in evolution for Homo Sapiens, so we'd better get used to it.