Note: All FilamentDirect.com filament comes in a sealed poly bag with 2 dessicant bags to keep your filament properly stored. So you really shouldn't have to worry about storage as long as you have not opened your filament!
It’s immensely important to store your filament properly - good filament means better prints and better prints are, obviously, what you want - you didn’t splash out on a 3D printer only to have it get jammed or have your print overly warp. Buying filament in bulk will save you money in the long run, but only if you store it properly.
The main problem anyone will have with storing filament is that moisture will eventually get into the plastic and form tiny bubbles within the filament. The heat of the injection syringe when the plastic moves through the printer causes the moisture bubbles to explode and will ruin a delicate print. To avoid this, try storing your filament in a waterproof container with an open container of rice inside, to soak up any moisture that does get in.
Another more minor problem that some people have is due to keeping their filament and 3D-printing cleaning chemicals close together. These can react with the filament through the air if they produce fumes. ABS, for example, is soluble in acetone and when kept in the same room with acetone will start to degrade due to the fumes that acetone produces.