Well, it's not my term, it was applied to me, and it was intended as an insult, or at least a pejorative. I don't think it applies at all, as in reality I'm really a pretty careful and deliberate photographer. When I have the opportunity, I can slow down to about five frames an hour - macro work, done indoors in controlled situations, on a tripod and focusing rail with a tilt/shift lens, for example. But I do a lot of sports, and in fact that's where I use up a lot of frames. One might even argue that I don't spend enough frames there. (One of my regular shooting partners is a pro, and he almost always shoots many more than I do.) If I were shooting 25k/yr as a part time landscape photographer that would be a clear sign of some uncritical decision making behind the viewfinder. And indeed I do macro, landscapes and portraits. But I also do motorsports, baseball, equestrian and occasionally some other things where the frames roll up pretty quickly. Wildlife, too.
> D4 ... not in the budget
Well of course - you did say $3000! But actually I didn't say to get a D4, just to wait until that generation comes out. Even on the steep learning curve, you've got a year left in the camera you have. But when the D4 comes out, I expect it to be the herald of a new generation - a new D400 and maybe a D800 will accompany it, and really those were the ones I was thinking of. That's one reason I encourage you to wait a year. The other is to climb the curve more to gain enough experience to know where to go next. As fast as she's going, it will still be a while before she really needs to move on.
> retire and ... photography professionally
I hear many echos of myself here, and that's one reason why I changed my recommendation over the course of several posts, as I learned more about your specific situation. You're new to Nikonians so probably wouldn't realize how rare that is, but I don't change 180 degrees very often. Particularly because I've been through this myself, I can see where this curve goes. She (and you, apparently) are already undertaking a wide variety of things, and entertaining the possibility of entering the profession, so my advice is to recognize where that's going and to plan your investments (think of them in those terms, as well as return on investments) accordingly.
_____ Brian... a bicoastal Nikonian and Team Member
My gallery is online. Comments and critique welcomed any time!