Yes, it looks like you have a boss there to fit a rack to, hoorah! Like you say, even if the Giant doesn't end up touring, a rack is just so useful, even if only to bungy your coat to when you get hot.
You're quite right about people being more informed - it's a slow uphill job, but there are people out there doing it. I worked for Company of Cyclists (Now called Get Cycling, and employing Spandex and Mickle from here) who ran tryout roadshows to try and promote cycling and let people know about the range of bikes out there, and what was best for what purpose. I think the trouble is, a bike is slightly regarded as a grown up toy. People who'd spend months researching a new car in all the magazines, or compare 800 stereo systems to get the right one, will just buy the cheapest thing they can find in Halfords that seems to vaguely fit, because they don't understand that there are different sorts, and that some are better than others for different things.
On the other hand, I agonise over bike purchases, but will buy the cheapest stereo I can get....
Montage's thing about old steel racers - he could be right - 'racer' is one of those terms that is quite flexible, I think. Sometimes it's just meant anything with drop bars. A steel frame should be comfortable enough, and if it does have bosses for rack and mudguards, it would probably make do.
Modern 'racers' (also called road bikes) tend to be designed to be stiff and fast, and have aluminium frames (or carbon, or titanium), and probably no bosses. That's the thing to avoid, for touring.
Main thing is, anything you get a chance to look at, check if it'll take rack and mudguards and have a ride to see if it's comfortable. Are you used to drop bars, BTW? (the sort that loop away and downwards, like race bikes) If not, they may take a bit of getting used to. I eventually decided I preferred 'normal' bars, so I have them now on my tourer (or will have, when it's rebuilt). That's another thing that can be altered to suit you.