X64 for me. I'm interested in desktop computing. And an i7 is way cheaper and faster than any arm stuff you can buy. Some time ago I saw a toshiba i7-laptop with 4 cores, 666Euros. Try to beat that with a top of the line ARM. In addition to that I could use Virtual Machines and save money and space. Running x64 emulators on ARM would be pretty pathethic. I don't need to spend thousands on a decent peecee, you can have it for the same price that ARM gear but X64 will run rings around any ARM machine. ARM is ok for kids' toys to play angry birds on a 70 tablet but as soon as you buy a low-end peecee (let's say 300) then ARM is pretty useless, slow and lacks apps. X64 is fast, cheap, flexible and more standard and we'll always have millions of available and useful machines. Even an old AMD XP1800 running at 1400Mhz runs rings around ARM stuff. Try to compile, try to launch eclipse, ARM is a toy and will continue in that state for some years. We are in 2012 and I can't see commercial ARM products that beat Apple Quad-G5 in speed (I mean doing real work, not some ramdon benchmark comparing a recent gfx core with an old Radeon9600
