I hit an interesting milestone in market trading this month: Since I haul all of my own stock that I then trade, I've now hauled 1 trillion isk (technically, more like 1.25t, as the above not include my second trader). And, I've hauled 1 trillion isk without "incident." A few gank attempts, sure, but no successful ganks after hauling for over a year. Of course, this does not imply that hauling is safe. With the active work of CODE. & co. in systems like Uedama and Niarja (both of which I pass through for some of my hubs) there has probably never been a more dangerous time to haul goods.
So how does one haul 1 trillion isk without being ganked? Well, not all at once, that's for sure. Being ganked is inevitable, however--there is no "perfectly safe" way to haul. Since I work from home quite frequently, hauling is something that I can do without devoting much attention to the game. I fully expect to get ganked one day, and it is a type of gameplay--particularly in the form of organized ganking and creative hyper-dunking--that I fully support and myself engage in.
I wrote a post about what ships I use to haul goods: http://evelostfound.blogspot.com/2014/07/safer-hauling.html That has stayed fairly constant, except I use freighters less and less, and when I do use a freighter I haul at off-hours, when the server population is low. I would estimate that 10% of my hauling, by isk, is done via freighter, 40% by blockade runner, and 50% via deep space transport.
Before hauling, I check the killboards in hot systems for ganking activity, particularly organized ganking. This isn't a perfect method (one could always be the first target of the day!) but waiting a day to haul through a hot system has likely saved me a few freighters.
Of the two or three gank attempts that have happened to me in my DST, their cause is due to a tornado having a cargo scanner but not a ship scanner. This is what a single tornado volley did to my shields (the OH did not go off in time--I was preparing for multiple tornados, just in case they were to show up):
Realistically, though, a single T3 can often kill a DST given how they are usually fit according to the killboards--no buffer tank, all cargo expanders, and so on. Hauling is a microcosm of the game itself: there is always, always risk any time you undock, but the game (via its sandbox gameplay) inevitably punishes laxity and ignorance and thereby (sometimes) rewards being careful and smart--or, at least, it rewards being a little more careful and smart than the player next to you, a feeling I've often gotten when jumping into Uedama in a scout or fast hauler and seeing a freighter, probably still afk, helplessly being bumped 200km off the gate. It really is a beautiful ecosystem.