I have no desire to fan the flames because the truth is we simply do not know what the future holds. It seems clear to me that SOMETHING is going to happen, but what it is and when it will occur, well, your guess is as good as mine.
For me personally, I've made the choice to stock up on atomizers and juices. I never, ever want to be in a situation where I have an excuse to go back to analogs. I feel quite certain that if I do not have a functional vaping device, I'll be right back where I was . . . smoking the cancer sticks.
My finances are such that it's not a terrible burden to stockpile atomizers and juices. If it were, I have a feeling I'd still be doing it, but the decision wouldn't be quite as much of a no-brainer.
If I were new to vaping and hadn't really settled into a model that I really loved, then I probably wouldn't be stockpiling parts yet. If money were really tight, then I wouldn't be putting big charges on my credit card or paying my bills late in order to stock up on parts.
If I had been vaping long enough that I felt this was truly something I wanted to continue doing, then I'd probably be looking at a mod as my next e-cig to avoid battery issues. (As Spikey noted, mods use non-proprietary batteries that you'll be able to get even if e-cig parts become unavailable.)
But, yeah, if you have a device you love and money isn't so tight that you're going to be getting behind on your bills, I'd be stocking up. I'm in it for the long haul--I have about 50 DSE901 atomizers, 25 penstyles, and maybe 6 of the 510 atomizers. As for liquid, I've stockpiled enough to last me about 1 1/2 to 2 years, about the shelf-life of liquid. I'm experimenting a bit with different no nicotine solutions to see if I can find one that is satisfying enough that I can eliminate my nicotine habit just in case liquids become difficult to find.
But note that I didn't stock up overnight . . . I've been vaping for almost 5 months, and I started building up my supplies shortly after I began vaping.