So, a $20 card adds handoff/continuity support. Sweet![url=http://i219.photobucket.com/albums/cc176/Ian2TG/ScreenShot2014-06-18at233703_zps1c514905.png]Image[/URL]
My 2011 MacBook Pro 15 has a 2012 bluetooth/Airport card in it, as that was all I could get when I repaired it. I get this in System Profiler on 10.10 DP2, so it looks like some Macs will be somewhat upgradable hardware wise.
Interestingly I remember hacking Airdrop back on Lion on an upgraded 2006 iMac with a 2008 Airport card in (so I could have wireless n) it and that worked flawlessly!