Personally, I think 32 bits is enough for any application I'd care to run. If you need more than a few GB of memory, IMO the application is being ridiculously wasteful. But YMMV -- if some people think it's fun to debug 16-digit hexadecimal numbers, I'll quote Mr. Knightly: "I have nothing to say against it, but that they shall not choose pleasures for me."
IMO 64 bits is for mainframe operating systems. For my personal use, I prefer something... well, more personal.
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used in Orion Spacecraft, part of NASA's Mars mission. Live radio show and live chat. Get your questions ready.
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