In Rick's book he says single tickets on the public transit are 1.7E and are good for one journey. On p461 when he talks about his "self-guided tram tour" he says "You can (and should) jump on and off as you go". At 1.7E a pop that would add up quickly, so is the ticket good for a fixed amount of time and not one boarding?
Also, even though page 458 lists single tickets as 1.7E on page 457 (Arrival in Vienna by Plane) it says you can get from the airport to Vienna by S-Bahn "(S-7 yellow, 3E)". Why wouldn't the price be 1.7E?