I just got the call. ?Picked-up but there was no response.  I really need to hone my 'call screening' abilities...  :(

Two calls from this number in less than half an hour; first time it said 'Unknown', second time, just the number. Like many others, I do not answer calls from numbers I don't recognize. If it's important, they'll leave a message. I suspected it was a political survey and I see from the responses below, it most likely was.

Hello, give us your number we will gladly call you!

These calls are being made across Canada from BC to Nova Scotia, it is not following any known phone lists so it would appear it is an auto-dialer which is simply dialing every possible number on known canadian area codes. Both WestJet and Air Canada are aware of the problem and their private security companies are working on it, and apparently the RCMP are aware of this across Canada as well.
It doesn't matter if you press a number or not, simply picking up just logs your number as active and able to be further scammed, that includes if your cell takes voicemail or if your answering machine picks it up when you are not home.

Just got a call ...told me i'm the winner of 100000 airmiles and to hold...then some videogame music played for 2 min....hung up and tried to call back and the number was out of service

I got part of a voice mail from this number last night. All I got was "Gift press one" It was on a old VoIP number that I have not used in months. This number was not registered on the NDNC list.