RAID recently was diagnosed as a dead technology. Some people in the industry call it a zombie technology. In other words, it's been declared dead, but it's still viable and functional. Other examples of zombie technology include the mainframe, UNIX, magnetic tape, magnetic disk drives, even Fibre Channel. These products have been declared dead for years, even decades in some cases, yet they continue to prosper.
If anything is dead about RAID, it's the hype and focus we saw about a decade ago. RAID's future is more transparent, yet with more enhancements. We're seeing distributed parity, dual parity, hybrid RAID schemes, horizontal and vertical striping, RAID on solid-state memory, network parity, among others.
Check out the entire RAID FAQ guide.