I'm running Yosemite on a MBP retina (12/2012) and iOS 8.1 on a brand spanking new iPhone 6 Plus: so it MUST be working!
I was going crazy with this AirDrop issue as well, until I noticed that in the finder window (when i was selecting "AirDrop") there's a really small blue writing "allow me to be discovered by:..." and then I could select "Everyone", "Contacts only" and "No One" (right under the blue AirDrop icon).
It was by default on "Contacts only".
It means that if you're not registered in your own Contacs list on your computer the iPhone (or iPad or iPod) can't see the computer itself since you're not register in the same Contact list as well.
Changing the setting on the computer to "Everyone" solved the issue as my MBP suddenly popped up on iPhone as AirDrop destination.
So basically if you're Airdropping from any iDevice to any Mac (or viceversa) be sure to have both systems set to be discoverable to"Everyone".
If only one of them is set on "Everyone" then it will be possible to AirDrop only towards the one that's set as "Everyone".
If both are set as "Contacts Only" then be sure that you're register in your own Contact's list, otherwise it ain't gonna work.
Quite clumsy from Apple not to explain a little better this thing and quite clumsy that on a Mac AirDrop is set as "Contacts only" by default.
I hope this is gonna help some of you people who's having this issue for some time now.