OK, this is probably going to wander slightly off-topic and even border on becoming a rant, but since that's never stopped me before, here goes.
Rangefinders, even the most sophisticated ones, don't look like "real cameras" to people raised on modern marketing; they've been fed the expectation (by the media and disappointingly the camera companies themselves) that the ONLY cameras for serious use are SLRs (whether 35mm or digital - medium format hardly gets a mention anymore, let alone large format). Let's face it, rangefinders DO bear more than a passing resemblance to the cheapo point-and-shoots which consumers are told can't produce "professional results". Most salesmen these days probably don't know the difference between the types either; they tend to be concerned with what they can sell the most of. Consider also what type of camera is recommended to beginning photo students. I can't recall seeing a single syllabus which suggested that anything other than a manual SLR would suffice for learning photography. Another point to consider: when was the last time you saw a reasonably priced rangefinder camera marketed to anyone who isn't already interested in photography?
I have to admit, I bought into all that hooey myself. What happened to free my mind? I noticed that a couple of photographers profiled in the
National Geographic Field Guide to Photography whose work I've long admired and wanted to learn from were carrying these funny little cameras called "Leicas" and swore by them. Curious, I did a little digging on the Internet and found this website. Intrigued, I bought one, tried it out, and found that for the way I like to shoot and the subjects I choose to shoot, rangefinders WORKED without the camera getting in my way. The rest, as they say, is history.
With all that said, photography is still ultimately about the image and not the equipment. If she wants to shoot with an SLR or digital camera, fabulous! If she wants to try medium format, rock on! If she decides to try a rangefinder, awesome! As long as she has the right equipment
for her to get the image she sees on film/paper/monitor, in the end that's really all that matters.