Windows 7, Apple iPhones, Twitter mania, Google's attempts at world domination, and the return of Steve Jobs -- it was a heckuva year for tech From Steve Jobs’ organs to Microsoft’s new OS, 2009 was a year of renewal. Over the past 12 months, Facebook emerged as the 900-pound gorilla of social networks, while Twitter grew from a geeky curiosity to a global sensation — despite the continuing lack of a viable business plan. Windows 7 finally put Vista in our rearview mirrors, while Bing tried to erase the memory of Windows Live Search. Apple successfully fought off an attack of the clones and dominated the mobile Internet — despite the AT&T albatross wrapped around its neck. In short, it was quite a year for tech. We’ve culled some of the more notable questions from a year’s worth of quizzes to test just how well you were paying attention. Ready to wow us? Good luck.1. Last September, Steve Jobs made his first official public appearance since returning to Apple. What did he publicly acknowledge for the first time?a. Apple’s noncompetitive hiring agreements with other tech firms b. His new liver is 30 years younger than he is c. AT&T’s cell service really does blow d. He has a twin brother named Bob Take the InfoWorld year-end news quiz Data Management