Actually, Apple is terrible at surprises. If they were good at it, sites like ThinkSecret wouldn't be able to accurately predict new product configurations and release dates so often.
I would speculate that the only real difference between Apple and most other companies, when it comes to product announcements, is that Apple is the only company that understands how to generate such incredible hype by "leaking" tidbits of information and then pretending not to know about it. By the time their products hit the market, the hype is generally so feverish that thousands upon thousands of people are willing to plunk down thousands of dollars for products they've neither actually seen nor even researched.