cell phones, ever year. hopefully i finally have the phone that i wont upgrade for at least 2 years
TV - we just bought a new one after E owned his for over 5. We went from a 32 to a 42 LCD flat. so we upgraded big time.
computers - every 5 or 7 years. its time for an upgrade now, in fact. I tend to run newer software so i do need a comp to keep up with me
video game consuls - generally about 2 years after they come out. We are still waiting to get a Wii, and we actually "down graded" to a N64. or cube. whatever its called. But we did buy the new playstation so we could have a blue ray DVD.
music - we both have Zunes, E''s is the first one he''s ever had, and mine is upgraded from about 4 years ago from a creative
speakers/stereo - we''re old school on this. I love old receivers and speakers, and fortunately there is a good speaker repair shop in Seattle.
My dad is a techie, so i always grew up wanting the latest and greatest!!