<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by CPYVR:
Email is not yet available at Aeroplan and would not be a valid document for transborder travel anyway.</font>
That's what I always thought too. However, a couple of days ago I asked a US INS inspector at YYZ T2 this question. I showed him a sample email from expedia.ca and asked (hypothetically) if he would accept this as proof of return ticket. He said "yes - it just needs to have your name on it."