[generalk]

  >  When I buy a ThinkPad, I intend to keep it for 5 years. 
  > My friends with MacBooks all replace them every 2-3 years.

Yeah that's one of the reasons I don't know if I'm comfortable getting one of the new Macbooks. I mean the Retina Display w/ 16 GB of RAM is lustworthy, but the RAM is soldered into place (thus the need to max it out at 16GB at purchase-time), the battery's glued in place, and the SSD is apparently replaceable but completely nonstandard.

But I'm confused about what to replace it with, and concerned that I'll miss some of the better OS X stuff. Keynote is fantastic for presentations. Never having to worry about hardware compatibility is pretty convenient.