A hyperintelligence can aggregate way more data that already exists than we can, and apply it more usefully.
People often seem to miss that difference. Machine intelligence isn't just us, but faster. The vanity of the Turing test struck me the other day. A machine is intelligent when it an pass for us. Are we supposed to be the be all and end all of intelligence?
A vastly greater working memory, attention span, etc., can make problems of search and integration much easier. At least at first, machine intelligence will be most effective when used in collaboration with people. We've already got a lot of human style intelligence in people - I'd rather get new and complementary abilities.
I wrote a blog post responding to Kevin Kelly that I'm fairly happy about. It summarizes some of the reasons why I figure that superintelligence is likely to be a fairly big deal. If you read it, please post your comments here.