Unless they drop the price soon we're going to move away from them. It sounds silly to argue over $15/user/month, but in comparison to Google Drive it's just started feeling too expensive. I really like the product, but I don't know if any product in a commoditized space can sustain such a price premium.
For Dropbox, it is their core business. For Google, it's a drop in their massive bucket of cash that comes from advertising. If business reliability matters to you, Dropbox seems comparatively better.
Dropbox is more likely to go under before Google Drive does.