I've reused oak with decent success. Typically, though, reusing is more to carry bugs over from batch to batch. If you're soaking in whiskey, you shouldn't get too much beer flavor carry-over, provided you're not going from a strong porter to a pale ale. Even so, in 5gal quantities, the oak flavor should outweigh the beer carry-over flavor. You're probably more apt to get yeast carry-over (without sanitizing).
As far as reusing, i just leave mine sit on a paper towel to dry, then into a mason jar for storage. In my opinion, the harsher you treat the oak over and over again (oven drying, sanitizing, etc), the more you're losing the oaky goodness from those specific chips/cubes. I just throw my cubes into the beer after primary fermentation is complete.