Just thought I'd throw my 2¢ in here.
I have 2 macs, a early MBP 2011 and a late 2012 iMac. The iMac works with continuity rather well, as soon as I logged into iCloud it started working. I bought a bluetooth adapter for my macbook, and of course, it doesn't support continuity.
Heres my theory:
Apple uses the VendorID of the bluetooth card to decide if it supports continuity. I've heard you can hack kexts to somehow edit this, but Im not totally sure if its possible.
On my macbook I did get the message that continuity was available and now if I go into bluetooth settings it sees my phone and if I try to remove it, it says its associated with my iCloud, so I can't. So now we know that iCloud does factor in to handoff.
Which leads me to this conclusion, which may or may not be true. Handoff, at least sending data, doesn't use bluetooth, instead it goes through iCloud. We've already seen that this works with the iCloud tabs in safari. I've also read that bluetooth can INSTANTANEOUSLY sent about 1.5 mbs of data if the two devices are relatively close. Then why does handoff take about 40 seconds to work? From what I've read in the developer documentation, it doesn't seem like the handoff packets they send back and forth only have a few kilobytes in them, so it shouldn't be as slow as it is. Thats what leads me to believe its actually going through iCloud and just uses Bluetooth to make sure that the devices are close enough. In the bluetooth settings on the iMac, it did not say that my phone and the iMac were connected, however they were paired. My Macbook also says that its paired with the computer, but not connected. (This can be found in system information under the bluetooth tab if you scroll down for a bit).
Of course this is all speculation, and I could totally be wrong, but I think they did mention something about iCloud in the keynote.
